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This Code of Practice (the Code) provides practical information on how to manage health and safety risks associated with respirable crystalline silica from engineered stone in your workplace.
Working with engineered stone can expose workers, and other persons, to the risks of respirable crystalline silica (silica dust). Exposure to silica dust can have serious health effects, including fatal lung disease.
For the purpose of this Code, engineered stone1 is an artificial product that:
Engineered stone does not include natural stone that has not been combined with other products or heat cured (for example granite and quartz in their natural state).
Engineered stone is also known as composite stone, manufactured stone, artificial stone, reconstituted stone or quartz conglomerate. The crystalline silica content in engineered stone varies widely but it can contain greater than 90 per cent crystalline silica, which is significantly greater than that found in natural stones.
Table 1 outlines the variation in silica content that can exist in different types of stone.
Type | Amount of silica (%) |
Marble | 2 |
Limestone | 2 |
Slate | 20 to 40 |
Shale | 22 |
Granite | 20 to 45 (typically 30) |
Natural sandstone | 70 to 95 |
Engineered stone | up to 97 |
For the purposes of this Code, the term engineered stone covers the entire product lifecycle, including:
1 Engineered stone does not include concrete, concrete products, cement products, fibre cement, bricks, blocks, pavers, autoclaved aerated concrete, roof tiles, wall and floor tiles that are ceramic or porcelain, grout, mortar, render and plasterboard.
Crystalline silica is the crystalline form of silicon dioxide, a naturally occurring mineral that forms a major component of most rocks. It is found in natural stones like granite and sandstone and is used to create artificial products like engineered stone and tiles.
When dust is created through natural or artificial means it comes in a range of sizes, from very small (less than 10 micrometres [µm] in diameter) to larger particles that can be seen with the naked eye. Dust that is less than 10 µm in diameter (Figure 1) is known as respirable dust as, when inhaled, it travels deep into the lungs.
Figure 1: Dust particle sizes (original image from Mining and Quarrying Occupational Health and Safety Committee).
In its solid form, such as the slab supplied to a workplace for fabrication, engineered stone does not have hazardous properties; it is the dust that is generated from engineered stone that has the potential to cause harm when it is breathed in.
The fabrication stage involves using mechanical processes such as cutting, grinding, trimming, drilling, sanding and polishing of the engineered stone to create a specific product ready to be supplied for installation. For example, creating a kitchen benchtop to size and cutting holes for positioning a sink and tap.
Once the fabricated engineered stone product is installed, further mechanical processes may be required, for example, minor cutting to enable a custom fit, or for maintenance purposes.
Cutting, grinding, trimming, drilling, sanding and polishing engineered stone products generates respirable dust containing crystalline silica (silica dust). When breathed in over time, silica dust can cause fatal lung disease. The risks are much greater where the engineered stone contains high levels of crystalline silica.
Workers fabricating, processing, installing, maintaining or removing engineered stone products without appropriate control measures in place may be exposed to high levels of silica dust (for example through dust or mist clouds). Workers can also be exposed to silica dust from poor housekeeping methods that disturb accumulated dust, including dry sweeping, using compressed air or high-pressure water cleaners and general-purpose vacuum cleaners not designed for use with hazardous dusts.
Silica dust is a significant health hazard for workers. Very small particles of silica dust cannot be seen under normal lighting or with the naked eye and stay airborne for long periods of time. When airborne, workers can easily inhale the small silica dust particles deep into their lungs where it can lead to a range of respiratory diseases, including:
Silica dust also increases the risk of developing chronic kidney disease, autoimmune disorders (such as scleroderma and systemic lupus erythematosus) and other adverse health effects, including an increased risk of activating latent tuberculosis, eye irritation and eye damage.
Silicosis is a serious, irreversible lung disease that causes permanent disability and can be fatal. Silica dust can be breathed deep into the lungs and, when silica dust comes into prolonged contact with the lung tissue, it causes inflammation and scarring and reduces the lungs’ ability to take in oxygen. Silicosis may continue to progress even after a worker is removed from exposure to silica dust. As the disease progresses, a worker may experience shortness of breath, a severe cough or general weakness. There are three types of silicosis (Table 2).
Table 2. Types of silicosis.
Silicosis type | Exposure type | Respiratory impact of exposure |
Acute | Can develop after short-term and very high levels of silica dust (for example less than one year, and after a few weeks). | Causes severe inflammation and protein in the lung. |
Accelerated | Results from short term exposure to large amounts of silica dust (1 to 10 years of exposure). | Causes inflammation, and protein and scarring in the lung (fibrotic nodules). |
Chronic | Results from long term exposure (over 10 years of exposure) to low levels of silica dust. | Causes scarring of the lung and shortness of breath. |
Damage to the lungs from silica dust and symptoms of disease (such as lung cancer, silicosis and progressive massive fibrosis) may not appear for many years. Workers may not show any symptoms, even at the point of initial diagnosis, which is why prevention and health monitoring are critical. Health monitoring requirements for workers who work with engineered stone are detailed in Part 3.3 of this Code.
There is no cure for silicosis. However, all silica dust-related diseases are preventable through using effective controls throughout the lifecycle of the product to eliminate or minimise exposure to silica dust at the workplace.
Duty holders with a role in managing the risks of silica dust when working with engineered stone include:
A person can have more than one duty and more than one person can have the same duty at the same time.
When working with engineered stone, a PCBU must eliminate risks arising from exposure to silica dust or, if that is not reasonably practicable, minimise the risks so far as is reasonably practicable to workers and other persons at their workplace.
The WHS Regulation includes specific requirements for a PCBU to manage the risks associated with hazardous chemicals, including air monitoring and health monitoring (see Part 3 of this Code).
More information about the classification of respirable crystalline silica can be found in the Hazardous Chemicals Information System (HCIS) on Safe Work Australia’s website.
The person with management or control of a workplace must ensure, so far as is reasonably practicable, that the workplace, the means of entering and exiting the workplace and anything arising from the workplace are without risks to the health and safety of any person.
The person with management or control of fixtures, fittings or plant at a workplace, must ensure, so far as is reasonably practicable, that the fixtures, fittings and plant are without risks to the health and safety of any person.
Officers, for example company directors, have a duty to exercise due diligence to ensure the PCBU complies with the WHS Act and WHS Regulation. This includes taking reasonable steps to ensure that the PCBU has and uses appropriate resources and processes to eliminate or minimise risks that arise from working with engineered stone; namely exposure to silica dust. More information on who is an officer and their duties is in the Interpretive Guideline: The health and safety duty of an officer under section 27 on Safe Work Australia’s website.
Designers, manufacturers, importers and suppliers of engineered stone used at the workplace must ensure, so far as is reasonably practicable, the engineered stone they design, manufacture, import or supply is without risks to health and safety.
More information specifically for designers, manufacturers, importers and suppliers is in Part 2 of this Code.
As defined in the WHS Act, workers include employees, contractors and subcontractors and their employees, labour hire workers, outworkers, apprentices, trainees, work experience students and volunteers. Workers have a duty to take reasonable care for their own health and safety and they must take reasonable care that their acts or omissions do not adversely affect the health and safety of other persons. Workers must:
Other persons at the workplace, like visitors, must take reasonable care for their own health and safety and must take care not to adversely affect other people’s health and safety. They must comply, so far as they are reasonably able, with reasonable instructions given by the PCBU to allow that person to comply with the WHS Act. For example, if engineered stone is being installed at a customer’s home by a PCBU, that home becomes a workplace. The homeowner and other people who enter the home while it is a workplace are other persons for the purposes of the WHS Act.
A PCBU must consult, so far as is reasonably practicable, with workers who carry out work for the business or undertaking and the HSR (if any), who are (or are likely to be) directly affected by a work health and safety matter. Worker input and participation improves decision-making about health and safety matters and assists in reducing work-related injuries and disease.
Workers are entitled to be represented in consultations by a HSR who has been elected to represent their work group.
Workers who work with engineered stone and the HSR (if any) must be consulted on health and safety matters, including, but not limited to:
When discussing health and safety matters with workers, workers must be provided with reasonable opportunity to express views before any decisions are made.
A PCBU must consult, cooperate and coordinate activities with all other persons who have a work health or safety duty in relation to the same matter, so far as is reasonably practicable.
Where there is more than one PCBU involved in work being carried out at the same location, each duty holder should exchange information to find out who is doing what task and work together in a cooperative and coordinated way, so risks are eliminated or minimised so far as is reasonably practicable.
An example of when multiple duty holders may need to consult, cooperate and coordinate is during installation of an engineered stone kitchen bench top in a home. During the installation, multiple PCBUs may carry out activities on the same site, such as electricians, plumbers, or cabinetmakers. They each have a duty to protect the health and safety of workers and other persons at the workplace and must therefore consult, cooperate and coordinate activities to ensure each person is made aware of what the others are doing, to identify the hazards and risks and decide who is best placed to take action to control the risks.
Duty holders’ work activities may overlap and interact at times. When they share a duty, for example a duty in relation to the health and safety of the same worker or workers, or are involved in the same work, they will be required to consult, cooperate and coordinate activities with each other so far as is reasonably practicable.
See the Code of Practice: Work health and safety consultation, cooperation and coordination for guidance on consultation.
The WHS Act requires that a PCBU ensures, so far as is reasonably practicable, the provision of any information, training, instruction and supervision that is necessary to protect all persons from risks to their health and safety arising from work with engineered stone that is carried out as part of the conduct of the business or undertaking.
A PCBU must ensure that information, training and instruction provided to a worker are suitable and adequate and have regard to:
A PCBU must also ensure, so far as is reasonably practicable, that information, training and instruction are provided in a way that is readily understandable by any person to whom it is provided. A PCBU should consider any special requirements of the workers, for example, information, training and instruction may need to be provided in a language other than English. Other considerations include the specific skills or experience, disability, literacy or age of the worker.
Workers must be trained and have the appropriate skills to carry out tasks safely. Training should be provided to workers by a competent person. A competent person is a person who has acquired through training, qualification or experience the knowledge and skills to carry out the task.
A PCBU should obtain any information related to the health hazards of engineered stone and any instructions on safe work practices available from the suppliers of engineered stone for use in instruction and training activities.
Training should be practical, and where relevant, include hands-on sessions, for example:
Information, training and instruction provided to workers who carry out work with engineered stone must include the proper use, wearing, storage and maintenance of personal protective equipment (PPE), and should also include information about, but not limited to:
A PCBU should review training regularly, particularly if there has been a change to the way in which work is performed, or a request is made by the HSR. For example:
‘Construction work’ is defined in the WHS Regulation as any work carried out in connection with the construction, alteration, conversion, fitting-out, commissioning, renovation, repair, maintenance, refurbishment, demolition, decommissioning or dismantling of a structure.
Clause 291 of the WHS Regulation sets out a list of construction work that is high risk for the purposes of the Regulations, and for which a safe work method statement (SWMS) is required. This includes work ‘carried out in an area that may have a contaminated or flammable atmosphere’.
The on-site installation of engineered stone is considered high risk construction work if the processes used to install, modify or repair the engineered stone such as, cutting, grinding, trimming, drilling, sanding, or polishing generate silica dust and contaminate the work area.
A SWMS must be prepared before carrying out any on-site installation of engineered stone that involves any processing, modification or repair of the engineered stone that may generate silica dust.
A SWMS is required because it helps a PCBU clearly communicate to all workers at the construction site any health and safety risks and how they will be managed. A SWMS is not required for work undertaken during fabrication of the engineered stone at a workshop.
A PCBU must prepare a SWMS, or ensure a SWMS has been prepared, before installation of the engineered stone starts. The person responsible for carrying out the on-site installation of the engineered stone is often best placed to prepare the SWMS in consultation with workers who will be directly engaged in the installation of the engineered stone and HSRs, if any.
If more than one PCBU has the duty to ensure a SWMS is or has been prepared, they must consult and cooperate with each other to coordinate who will be responsible for preparing it.
There may be situations when different types of high-risk construction work occur at the same time at the same workplace. In this situation, one SWMS may be prepared to cover any high-risk construction work activities being carried out at the workplace.
Alternatively, a separate SWMS can be prepared for each type of high-risk construction work. If separate SWMS are prepared, consider how the different types of work activities may impact on each other and whether this may lead to inconsistencies between control measures.
The on-site installation of engineered stone will often be carried out in connection with a construction project. In this instance, the SWMS must consider the WHS management plan prepared by the principal contractor of the construction project.
A PCBU must provide the principal contractor with a copy of the SWMS before high risk construction work starts. If not made available, the principal contractor would need to take reasonable steps to obtain a copy of the SWMS before construction work commences.
More information on multiple and shared duties can be found in the Code of Practice: Construction work.
The content of a SWMS should provide clear direction on the control measures to be implemented. There should be no statements that require a decision to be made by supervisors or workers. For example, the statement ‘use appropriate PPE’ does not detail the control measures. The control measures should be clearly specified.
The SWMS must be accessible and understandable to any individual who needs to use it. It is important that those who need to carry out work in accordance with the SWMS understand the detail of the SWMS and what they are required to do to implement and maintain risk controls. For example, it should consider the literacy needs and the cultural or linguistically diverse backgrounds of the workers.
A SWMS must include the following information:
If high risk construction work is not carried out in accordance with the SWMS for the work, the PCBU must ensure that the work is:
More information about a SWMS for high risk construction work and a SWMS template can be found in the Code of Practice: Construction work.
Designers, manufacturers, importers and suppliers of engineered stone all play important roles in ensuring risks to workers and other persons are eliminated or minimised.
This is because in these early phases of the product lifecycle there is greater scope to:
Providing information to downstream duty holders (like PCBUs who fabricate or install engineered stone products) is a key factor in assisting them to meet their duty to manage health and safety risks. Information should be passed on from the designer and/or manufacturer to the importer, supplier and the end user.
Designers, manufacturers, importers and suppliers must ensure, so far as is reasonably practicable, that the engineered stone they design and manufacture, is without risks to the health and safety of persons at the workplace or within the vicinity of the workplace.
Designers, manufacturers, importers and suppliers must carry out, or arrange the carrying out of, any calculations, analysis, testing or examination that may be necessary to meet their duties.
Designers, manufacturers, importers and suppliers must give adequate information to downstream users of:
This information can be provided in the form of a label, product information sheet or a safety data sheet.
Importers and suppliers can obtain information about the engineered stone products that they are importing or supplying from the designer or manufacturer.
Designers, manufacturers, importers and suppliers do not have a duty to provide this information as a safety data sheet for solid products that contain crystalline silica, such as engineered stone. However, safety data sheets are an effective way to communicate information downstream about the risks when working with engineered stone. It is considered good practice to make them available.
If requested, designers, manufacturers, importers and suppliers must, so far as is reasonably practicable, give relevant information to users, and provide any amendments or updates to this information.
More information about safety data sheets can be found on the Safe Work Australia website.
An exposure standard represents the airborne concentration of a particular substance or mixture that must not be exceeded. It does not represent a line between a ‘safe’ and ‘unsafe’ concentration of an airborne substance or mixture. The exposure standard does not eliminate risk of disease and some people might experience adverse health effects below the exposure standard.
A PCBU at a workplace must ensure that no person at the workplace is exposed to a substance or mixture in an airborne concentration that exceeds the exposure standard for the substance or mixture. The duty to ensure the workplace exposure standard is not exceeded is absolute and not qualified by ‘so far as is reasonably practicable’.
This means that a PCBU must ensure that no person at the workplace is exposed to a hazardous chemical, such as crystalline silica, at a concentration above the workplace exposure standard.
The workplace exposure standard for respirable crystalline silica is an eight hour time weighted average (TWA) of 0.05 milligrams per cubic metre (mg/m3).
A TWA is based on exposure that happens over an eight hour working day followed by 16 hours of no exposure, over a five day working week.
To comply with the WHS Regulation, it may be necessary for the PCBU to adjust the TWA to compensate for greater exposure during longer work shifts and decreased time between shifts. Situations where the TWA may need to be adjusted include where workers have:
A competent person, such as a certified occupational hygienist, should be engaged to adjust the workplace exposure standard to account for shift variations or longer working weeks.
The workplace exposure standard must not be adjusted upwards, even for shifts less than eight hours.
More information can be found in the Guidance on interpretation of Workplace exposure standards for airborne contaminants on Safe Work Australia’s website.
A PCBU must ensure that air monitoring is carried out to determine the airborne concentration of silica dust in a worker’s breathing zone, if necessary, to determine:
Air monitoring can also be used to:
Air monitoring does not prevent disease and is not an alternative to implementing effective control measures.
A PCBU should ensure air monitoring is conducted by an independent, competent person. For example, a certified occupational hygienist or a person with recognised equivalent competency under an international certification scheme.
Air monitoring to determine a worker’s exposure involves measuring the level of silica dust in the breathing zone of workers using a personal sampler during their usual shift activities, including routine breaks. Figure 2 shows an approximation of a worker’s breathing zone.
Figure 2: Worker’s breathing zone.
When commencing work with engineered stone, a PCBU should undertake baseline air monitoring to ensure that silica dust levels do not exceed the workplace exposure standard and that any risks to workers’ health are minimised. Air monitoring should be repeated to ensure the air monitoring results are accurate and representative of the work being undertaken.
After a baseline is established, air monitoring should be undertaken:
Examples of triggers for undertaking additional air monitoring include:
There are certain roles that are likely to have a high exposure to silica dust. These include (but are not limited to):
An air monitoring report is prepared by a competent person, such as a certified occupational hygienist and should include:
The air monitoring report should be made available to a WHS inspector on request and to a registered medical practitioner carrying out or supervising health monitoring.
Additionally, a PCBU must ensure that the results of air monitoring carried out are:
Static or fixed position monitoring may be undertaken at fixed workplaces, such as fabrication workshops, to determine general background levels of respirable crystalline silica outside of a worker’s breathing zone.
Static monitoring involves taking samples of air from fixed locations outside the area where the engineered stone is being processed.
Static monitoring can help in determining the design of risk controls or the effectiveness of existing risk controls, however it should not be used as an indicator of actual worker exposure to respirable crystalline silica.
Health monitoring is the monitoring of a person’s health to identify changes in their health status as a result of exposure to certain substances. Health monitoring is important for workers who work with engineered stone because exposure to crystalline silica through silica dust poses a significant risk to their health.
Health monitoring for workers exposed to crystalline silica primarily involves screening the changes in a worker’s body that may indicate the development of silica related-injury, illness or disease. Health monitoring is necessary to:
More information about what ‘significant risk’ means can be found in the Health monitoring for persons conducting a business or undertaking guide on Safe Work Australia’s website.
A PCBU must organise and pay for health monitoring if there is a significant risk to the health of their workers because of exposure to silica dust at the workplace.
This means that a PCBU must provide and pay for health monitoring for all workers involved in fabrication and installation of engineered stone. Examples of workers that the PCBU should provide health monitoring for include:
A PCBU should also consider providing health monitoring to other workers who might be exposed to silica dust from these processes. This includes workers who are exposed to dust while cleaning work areas or equipment, maintenance workers, salespeople, or those who perform administrative work in the vicinity of fabrication and installation.
A PCBU should provide health monitoring before a worker starts work to establish a baseline from which changes can be detected (unless the worker has participated in health monitoring within the previous two years and the results of the tests are available). From the initial health monitoring date, a worker’s health should then be monitored at least annually.
At the end of a worker’s time working with engineered stone, for example, before retirement or before the worker’s duties change permanently, a final medical examination should be carried out by the registered medical practitioner carrying out or supervising the health monitoring.
As workers may work for multiple PCBUs it is important to consider when they last participated in workplace health monitoring and consult with a registered medical practitioner to avoid them having excessive radiation.
Some workers may be reluctant to participate in health monitoring. This may be due to anxiety about the testing and medical results or the impact the results may have on their job, or both.
Under the WHS Regulation, a PCBU has a duty to provide health monitoring to workers where they conduct ongoing work at a workplace generating silica dust and there is a significant risk to their health because of exposure to silica dust. If a worker refuses to participate in health monitoring, a PCBU should first try the steps outlined below. If the worker still refuses health monitoring, a PCBU may take action to meet their duties under the WHS laws by removing the worker from the task or role that involves exposure to silica dust.
When considering the removal of a worker from the task or role, the PCBU should seek appropriate advice to ensure any action taken is consistent with other workplace laws.
A PCBU should encourage workers to participate and provide them with information and training on the purpose of health monitoring. Early detection of health effects can lead to an early diagnosis or treatment and prevent more serious and life-threatening conditions from developing.
Supporting a worker in these circumstances can be achieved by:
Conversations with workers about their individual health monitoring should be held privately to maintain confidentiality.
A PCBU must also consult with their HSRs about health monitoring. They may also assist in this process and encourage workers to participate in health monitoring.
When providing health monitoring, a PCBU must:
Under WHS laws, the minimum requirements for health monitoring for crystalline silica through exposure to silica dust are:
All full-size PA chest X-rays should be taken in a specialist radiology practice or hospital department. The X-rays should be read by a radiologist who meets the reporting requirements and competencies of the Royal Australian and New Zealand College of Radiologists or is qualified as a ‘B reader’. A B reader is a radiologist who has undertaken specialised training to detect dust lung diseases such as silicosis, coal workers pneumoconiosis, mixed dust pneumoconiosis and progressive massive fibrosis (PMF).
High-resolution computed tomography (HRCT) is more sensitive and effective than X-rays in the early detection of silicosis. A low dose HRCT scan of the chest (non-contrast) may be used by the registered medical practitioner supervising or carrying out the health monitoring, depending on the worker’s history and levels of silica exposure. Given the high risks posed by working with engineered stone, low dose HRCT may be used instead of, or as an adjunct to, X-ray. Alternative imaging methods are being developed and may also be considered.
More information on health monitoring workers for exposure to crystalline silica can be found in the Health monitoring guide – crystalline silica on Safe Work Australia’s website.
A registered medical practitioner with experience in health monitoring must undertake or supervise the health monitoring. The Royal Australasian College of Physicians website has a list of suitable practitioners. However, a PCBU may decide other doctors may have the necessary experience required to carry out or supervise health monitoring for their workers. A PCBU must consult their workers when selecting a registered medical practitioner and their preference should be considered if they request a particular doctor.
The following information must be supplied by the PCBU to the registered medical practitioner carrying out or supervising the health monitoring:
A PCBU should also provide the registered medical practitioner with any available air monitoring reports and risk assessments to assist them with carrying out health monitoring.
A PCBU must take all reasonable steps to obtain a health monitoring report from the registered medical practitioner who carried out or supervised the health monitoring. The health monitoring report should only contain information relating to the health monitoring that was commissioned by the PCBU.
The health monitoring report must include:
After a PCBU has received the health monitoring report from the registered medical practitioner, they should act on the results, recommendations and advice contained in it.
After receiving the report, a PCBU must provide copies as soon as practicable to:
Workers should provide their personal general practitioner (GP) with a copy of the health monitoring report and retain a personal copy along with any exposure history, particularly when the worker moves to other employment. This will assist a registered medical practitioner carrying out or supervising any further health monitoring to compare any previous results with new test and examination results.
The health monitoring report must not be disclosed to any person without the worker’s written consent, unless disclosure is required under the WHS laws.
The control measures at the workplace must be reviewed and revised (if necessary) if the report indicates that a worker is experiencing adverse health effects or signs of illness as a result of exposure to silica dust.
A PCBU must ensure that health monitoring reports for a worker are:
Treatment programs for adverse health effects should only be discussed between the worker and the registered medical practitioner and should not be included in the health monitoring report that is provided to the PCBU. If the health monitoring report includes health information other than what is required to fulfil the duties, or for which consent has not been given by the worker, the PCBU should return the report to the registered medical practitioner, informing them of the error.
More information about health monitoring reports can be found in the Health monitoring for PCBUs guide on Safe Work Australia’s website.
Risks arising from working with engineered stone must be eliminated or minimised so far as is reasonably practicable to protect workers and other persons against harm.
Risk management is a proactive, systematic process that helps a PCBU plan and respond to potential hazards and their associated risks in the workplace. It involves four steps:
A hazard is a situation or thing that has the potential to harm a person.
For engineered stone, the hazard is the silica dust generated through certain mechanical processes.
To identify the likely sources of silica dust, it is important for a PCBU to consider the following aspects of the workplace and their interactions:
This may be achieved by:
A risk assessment involves considering what could happen if a worker is exposed to a hazard and the likelihood of it happening.
Hazards have the potential to cause different types and severities of harm, ranging from minor discomfort to a serious injury, illness, disease or death. Exposure to silica dust can adversely affect a worker’s health, including developing silicosis, progressive massive fibrosis, chronic obstructive pulmonary disease, chronic bronchitis and lung cancer.
Assessing the risks will help to:
The nature and severity of risks will depend on various factors, including the:
The potential of exposure of administrative workers to silica dust at fabrication workplaces should also be considered. These workers may be exposed if:
A PCBU should review the information on the product labels, and any available safety data sheets, to assist in determining the type and severity of the harm. The following questions may help a PCBU to assess the risk:
A silica dust control plan is a practical tool for a PCBU that is informed by a risk assessment. It can help a PCBU identify all potential tasks that may result in exposure, or possible exposure, to silica dust and the control measures to eliminate or minimise that exposure.
A silica dust control plan should consider ways to:
A silica dust control plan should include details on:
Where a PCBU has decided to develop a silica dust control plan, it must be developed in consultation with workers involved in carrying out the tasks and the HSR, where there is one.
A PCBU may also share the silica dust control plan with the registered medical practitioner carrying out or supervising health monitoring. This will allow the registered medical practitioner to identify any possible source of silica dust exposure, taking into account the control measures in place.
A template for a silica dust control plan is provided at Attachment B.
A PCBU must eliminate risks arising from exposure to silica dust, or if that is not reasonably practicable, minimise the risks so far as is reasonably practicable to workers and other persons at their workplace.
A good way to meet this duty is to apply the hierarchy of control measures (Figure 3). The hierarchy ranks control measures from the highest level of protection and reliability to the lowest.
Dry cutting, trimming, drilling, sanding, grinding or polishing engineered stone without effective controls generates very high levels of silica dust.
A PCBU must not direct or allow workers to undertake uncontrolled dry cutting or processing of engineered stone. This will expose workers and others to levels of silica dust that would be expected to exceed the workplace exposure standard and is a serious risk to health.
Figure 3: The hierarchy of control measures.
For the purposes of this Code, elimination means completely removing all exposure to silica dust at the workplace.
For example, a PCBU can:
Silica dust will not be generated if the engineered stone installation is completed without further cutting, grinding, trimming, drilling, sanding, or polishing on-site.
Engineered stone that has been completely fabricated in a workshop with no additional cutting or fabrication required on-site poses a minimal risk of exposure to silica dust.
Eliminate the need for cutting, grinding, trimming, drilling, sanding, or polishing during installation by:
If elimination is not reasonably practicable, a PCBU should consider the following controls in the order set out below:
The control measures a PCBU applies may change the way work is carried out. In these situations, a PCBU must consult the workers and where applicable, their HSR, to develop safe work procedures and provide the workers with training, instruction, information and supervision on the changes.
Further guidance on the risk management process and the hierarchy of control measures is in the Code of Practice: How to manage work health and safety risks.
Substitution is where a different product, chemical or work process is used that is less hazardous and therefore has a lower risk than the engineered stone that was previously used.
Substitution can be an effective way of managing the risk of silica dust. For example, engineered stone can be substituted with a product that contains a lower percentage of crystalline silica such as, wood or laminate.
Care should be taken to ensure any new materials that are substituted do not introduce new hazards such as other hazardous chemicals.
Isolation is a way to separate the workers from silica dust. It is an effective control measure that can also be used in combination with engineering controls (see below) to reduce the number of workers potentially exposed to silica dust. For example, installing barriers between workers and machines that produce silica dust, both for workers generating the dust and workers nearby, such as those in adjacent offices.
Isolation can be achieved through:
Figure 4: An example of an isolation booth used for automated wet cutting.
Engineering controls use physical methods to change the characteristics of a task, including mechanical devices or processes that eliminate or minimise the generation of dust and minimise it becoming airborne. For example, a combination of engineering controls like LEV, on-tool extraction or water suppression may be required to minimise exposure from each dust generating process.
When considering and using engineering controls, be aware of other hazards that may be introduced. As many engineering controls are motorised, a PCBU should be aware of noise and vibration levels at their workplace and issue personal hearing protection as needed.
Water suppression uses water at the point of dust generation to dampen down or suppress dust before it is released into the air. Powered hand tools and equipment fitted with water feeds are available, including grinders and polishers, and large machinery including bridge saws, routers or polishing machines.
The equipment or machinery used for water suppression should:
Only tools and machinery that have been designed for use with water attachments should be used with water suppression. Handheld spray bottles, sponges or garden hoses are inadequate at suppressing silica dust. They are also dangerous if used with power tools that are not designed for use with water.
While water suppressed machinery and tools provide an effective means of reducing exposure to silica dust, their use needs to be controlled to ensure other hazards are not created. Potential hazards arising from the use of water suppression are electrical hazards, water mist hazards and recycled water hazards.
A PCBU must eliminate electrical risks or, if that is not reasonably practicable, minimise the risks so far as is reasonably practicable. When working with water suppression machinery and tools, electrical hazards can be introduced. A PCBU should:
As a consequence of applying water to power tools with rotating blades, contaminated water mist can be generated.
This water mist can expose workers to silica dust by:
If recycled water is used for water suppression, this may introduce an additional risk for workers. Without an appropriate filtration system, there is a risk that the continual recycling of water will increase the concentration of silica dust in the water over time, and subsequently the level of silica dust in the mist generated from water suppressed activities.
More information on managing the risks of recycled water can be found in section 6.2 of this Code.
Silica dust carried in the air or in water mist generated from water suppression can be further controlled through isolation controls such as guards, enclosures and barriers. In addition to those controls, administrative controls and respiratory protective equipment (RPE) should also be used. These controls include:
Routine maintenance and cleaning will help to ensure guards continue to work effectively.
LEV is designed to remove airborne contaminants from the air before they reach the breathing zone of workers. It is the most effective control for large quantities of silica dust when it is applied close to the source of generation.
For drills, routers, saws and other equipment, an appropriately designed LEV should be fitted. The manufacturer of on-tool extraction and LEV equipment can provide information about how the equipment captures dust to determine its suitability for a particular workplace.
A simple LEV system most commonly comprises of:
While these controls may reduce background levels of silica dust, they are not as effective in reducing exposure to silica dust for workers performing high exposure tasks. High exposure tasks should be performed using on-tool controls that suppress or capture dust at the source, such as integrated water suppression or dust extraction.
If there is too much distance between an extraction unit and the dust generation point, the capture strength or velocity of extraction at the point of dust generation is too low to adequately capture the silica dust generated.
For extraction to be effective, the cutting point needs to be close to the extraction hood. The nature of the work may not allow this, or it may require the worker to constantly reposition the work piece or hood. For example, a stonemason cutting a sink hole into a stone benchtop is regularly moving and turning the tool, which generates dust in a range of directions and angles.
Figure 5: Operational view of local exhaust ventilation.
On-tool LEV systems can include a shroud, an on-tool hose attachment and a vacuum extraction system. The dust or mist is collected within the shroud and is then drawn into the hose attachment to the vacuum, where it is extracted, filtered and discharged. When correctly designed and used a LEV system can both capture and contain dust or mist generated from engineered stone (Figure 6).
Figure 6: A worker cutting/grinding with on tool dust extraction.
Where the engineered stone slab can be lifted, a sacrificial backer-board or spoil-board should be placed under it during cutting or trimming. This prevents the release of dust below the slab and increases the effectiveness of on-tool dust extraction by LEV. Medium-density fibreboard or particleboard are suitable for this purpose.
Silica dust is very abrasive to LEV equipment. Regularly inspecting LEV equipment for damage will help ensure it is effective and fit for purpose.
Improving the general ventilation to a room or building may help reduce the concentration of contaminants in the air. However, ventilation should not be relied on to ensure silica dust exposure is controlled. Other controls must also be used to prevent the release of silica dust into the air and adequately protect workers and others in the vicinity from exposure to silica dust.
The workplace should have an adequate supply of fresh air. For on-site installation, processes that generate silica dust may be undertaken outside, provided the contaminated dust does not travel in the direction of other workers or premises. When working indoors, windows and doors within a room or building should be open to provide general ventilation. Fans may support the movement of air, but it is important that air streams are directed appropriately. Fans should be arranged so that streams of clean air are drawn past workers and contaminated air streams are drawn away from workers and ensure contaminated air is not directed towards others, for example, workers or adjacent businesses.
Wet slurries should be cleaned up before fans are used to prevent them from drying and creating potential dust hazards.
More information about natural ventilation at the workplace can be found in the Code of Practice: Managing the work environment and facilities.
Administrative controls are used to provide additional protection after implementing higher level controls such as substitution, isolation and engineering.
Administrative controls are work practices or procedures designed to minimise exposure to a hazard. For example, routinely cleaning the work area and vacuuming residual dust from clothing.
Due to the risks of silica dust when working with engineered stone, administrative controls on their own will not provide enough protection from exposure to silica dust. They should only be used in combination with and to support higher level control measures.
Administrative control measures rely on human behaviour and supervision to be effective.
The layout of engineered stone processing workshops needs to be designed to minimise exposure to and contamination from silica dust generated in neighbourhood work areas. For example, by including enough distance between workstations and positioning work areas for each stage of processing in sequence.
The way in which work is conducted can influence the generation of silica dust and worker exposure. While the use of higher order controls such as water suppression and LEV are critical to minimising worker exposure to silica dust, the following work practices may assist in reducing exposure:
Workers’ use of power tools, equipment and other machinery will influence the amount of silica dust that is generated.
Before plant or equipment is used in the workplace, workers and other persons who are to use it must be provided with the information, training, instruction and supervision necessary to protect them from silica dust and any other risks arising from its use.
Safe work procedures should be developed that include instructions on:
In addition to safe work procedures, warning signs (Figure 7) must be used to communicate silica dust hazards or the required PPE, if such signs are required to control the risks of silica dust.
Figure 7: Dust warning signs.
PPE refers to anything used or worn to minimise risk to workers health and safety, for example, protective footwear, eyewear and RPE such as powered air purifying respirators (PAPR).
If PPE is to be used to minimise the risk of exposure to silica dust, the PCBU must provide the appropriate PPE to workers at the workplace, unless this PPE has been provided by another PCBU.
PPE should only be considered after implementing substitution, isolation, engineering and administrative controls. It should only be used in combination with, and to supplement higher level control measures.
PPE should never be relied on as the sole means to protect workers from silica dust, as it does not control the hazard at the source and is the least effective at minimising risks when used on its own.
Using PPE relies on human behaviour and supervision to be effective.
It is a good idea to establish a system to manage workers’ use of RPE. The system should include:
A PCBU must ensure RPE is selected to minimise health and safety risks. This includes ensuring the RPE is:
When determining suitability, the protection factor assigned to the RPE must be sufficient to provide protection. The RPE filter must also be suitable for silica dust.
When using a tight-fitting respirator, it must have an effective face seal to ensure contaminated air does not leak into the respirator and is not breathed in by the worker. This means they should be clean-shaven or only have facial hair that does not interfere with the fitting surfaces or the respirator valve. As everyone’s face is a different size and shape, there is no ‘one size fits all’ tight-fitting respirator. Fit testing each worker and their RPE before they commence dust-generating work will help ensure RPE is effective.
For workers who want to keep facial hair that may interfere with the operation or proper fit of a tight-fitting respirator (for example a closely trimmed beard), a PAPR with a loose hood may be suitable.
Workers using handheld equipment for grinding and polishing tasks, in combination with effective engineering controls, should wear respiratory protection.
The following questions should be considered when choosing RPE:
More information about PPE can be found on the Safe Work Australia website.
Fit testing is essential to make sure the RPE works correctly and is comfortable to wear with other PPE that may be needed for the task. Fit testing measures the effectiveness of the seal between the respirator and the worker’s face. If there is not a good seal contaminated air, potentially containing silica dust, could leak into the respirator and be breathed in by the worker.
There are two types of fit testing that can be carried out:
Quantitative fit testing results are more objective than qualitative testing because some workers have difficulty with their ability to taste or smell. This can result in a ‘false pass’ and worker health not being adequately protected. Full face respirators and PAPR should be fit tested using the quantitative method.
All fit testing should be carried out by a competent person, manufacturer, supplier or consultant:
More information about who a competent person is can be found below.
For PPE to be effective, workers who are required to wear tight-fitting respirators should be clean shaven. If they cannot be clean shaven, ensure:
It is also important to ensure clothing, makeup, dental fixtures and jewellery do not interfere with the respirator seal or inhalation/exhalation valve operation.
A written record of fit tests carried out for each worker should be kept and shared with the worker after fit testing is complete. The record should include the:
Hood and head top type PAPRs do not require fit testing as they cover the whole head and do not rely on a tight seal.
Fit testers should be properly trained and proficient in the fit test method being used. Relevant competencies of a fit tester may include:
When issuing RPE, training must be provided to ensure that workers correctly use and maintain the RPE. Training can be carried out by:
Training in the use of RPE should cover the following:
Ongoing training and supervision may be required to ensure workers correctly use RPE. Workers must also take reasonable care for their own health and safety, comply with any reasonable instruction, and cooperate with any reasonable policy or procedure of the PCBU relating to health or safety. This means a worker must use and wear RPE in accordance with any workplace policy and information, training or reasonable instruction given.
Fit checking enables workers to take reasonable care of their own health and safety while working with engineered stone.
A fit check is a quick check to ensure a fit tested respirator is properly positioned on the face and there is a good seal between the respirator and face. Fit checks do not replace the need for a fit test. Workers should follow the respirator manufacturer’s instructions on how to carry out a fit check.
Fit checking is the responsibility of the worker. Workers must be trained on how to carry out a fit check for their tight-fitting RPE. They should undertake a fit check every time they use a tight-fitting respirator to ensure they are using and wearing RPE in a way that will protect their health and safety.
In addition to respirators, workers may need other PPE depending on the work task. A risk assessment should be conducted to decide the PPE required for workers.
The PCBU should assess the conditions likely to affect the health and safety of workers and ensure suitable PPE and appropriate training is provided before any work generating silica dust commences.
Other types of PPE that can be used to minimise exposure to silica dust include:
Appropriate protective footwear and clothing will protect workers’ clothing from silica dust, including water and mists containing dusts. Note that the use of gloves could be an entanglement hazard when using high-speed power tools.
A hard hat and hearing protection will provide protection and may be recommended to manage other risks associated with the engineered stone fabrication process.
When selecting other types of PPE, it is important to ensure that the PPE does not interfere with the effectiveness of RPE.
Figure 8: Personal protective equipment.
A combination of control measures should always be used to control the risk of silica dust when working with engineered stone.
This may include a combination of isolation, engineering controls, work practices and procedures and PPE. For example, a PCBU could consider a combination of water suppression, a LEV system, shift rotation and RPE. It is recommended that with any combination of controls to minimise silica dust, that RPE is provided and worn correctly for the full duration of the task to manage any residual dust.
If a PCBU relies solely on one control measure such as PPE or water suppression alone, there may be a significant risk to their workers’ health and they may be breaching the WHS laws. It has been shown that solely relying on PPE or water suppression does not adequately protect workers from the risks of silica dust.
All control measures must be maintained so they remain effective. This includes ensuring control measures are fit for purpose, suitable for the nature and duration of the work, and installed, set up and used correctly.
For example, a PCBU should conduct daily start up checks to ensure that:
A PCBU should routinely monitor the workplace for signs of visible dust on work surfaces or clothing as that may be an indication that some controls are not working effectively.
Silica dust is abrasive and can damage and wear plant, including engineering controls.
Plant must be routinely inspected, maintained and repaired according to the manufacturer’s specifications or, in the absence of such specifications, in accordance with a competent person’s recommendations.
Inspection of plant should identify any:
Hand-held powered tools should be regularly inspected, repaired or replaced when necessary, and any damaged or worn parts (such as grinding wheels) identified should be replaced.
A system of routine daily checks on plant and equipment designed to control dust should be implemented to ensure they are working effectively. Failures or problems identified should be rectified and workers should be encouraged to report concerns to the PCBU.
More information on plant inspection and maintenance can be found in the Code of Practice: Managing risks of plant in the workplace.
A PCBU must ensure that RPE is maintained, repaired or replaced so that it continues to be effective. A competent person should administer an RPE maintenance program in accordance with the manufacturer’s instructions.
A maintenance program should include procedures for:
An RPE maintenance program should also consider the environmental conditions the RPE is being used or stored in (for example, hot work vehicles) as the rubber seals may deteriorate and require replacing more frequently.
A PCBU must routinely review the control measures they have put in place to ensure they are effective and protect the health and safety of their workers.
Undertaking air monitoring to measure the airborne concentration of silica dust in the workplace is one way to check the effectiveness of controls.
If control measures are not working effectively, a PCBU must revise them to ensure effective risk control measures are implemented. A PCBU can use the same steps that were taken during the initial hazard identification to check control measures.
A PCBU must consult with their workers and, where applicable, their HSRs. They should consider:
If problems are identified, a PCBU should go back through the risk management steps, review information and make further decisions about risk control.
More information on the risk management process and the hierarchy of control measures can be found in the Code of Practice: How to manage work health and safety risks.
The proper clean-up of the workplace, including the decontamination of clothing and PPE, and the correct disposal of silica contaminated material, play an important role in further minimising exposure to silica dust for workers, or others in the vicinity of the workplace.
Regular cleaning should be undertaken to prevent the build-up of dust on floors, walls, other surfaces and equipment. Cleaning should be conducted at least daily, ideally at the end of the working day. Workers should wear RPE and use good housekeeping practices when cleaning. The wearing of RPE throughout the cleaning process will reduce the risk of workers being exposed to silica dust or contaminated water mist.
To ensure good housekeeping practices:
Dry sweeping methods, such as using brooms, or using compressed air to clean up accumulated dust, should never be used. These methods can recirculate silica dust into the air. Household vacuum cleaners are not designed for use with hazardous dusts and should never be used where silica dust is or may be present, even if they have a HEPA filter.
Dusty clothing and PPE can expose workers and others to silica dust. PPE should be cleaned after use to ensure that silica dust does not accumulate. Information about maintaining and cleaning PPE should be sourced from the manufacturer or supplier.
Examples of how exposure to silica dust carried on PPE and work clothes can be minimised include:
When working outdoors, the ground can be covered with plastic sheeting and remaining dust can be removed using the above methods.
More information about managing facilities at the workplace can be found in the Code of Practice: Managing the work environment and facilities
Wet slurry is the resultant waste from water suppression. This slurry has the potential to build up from continuous processing using water suppression on equipment and machinery. The slurry is not hazardous while wet. However, if it dries, the dust can become airborne when disturbed and expose workers and others.
Wet slurry can be managed by:
Any wet slurry that is de-watered so that it is still wet, but of cake-like consistency, should be disposed of in a way that minimises the risk of dust being redistributed over the workplace. This may include covering the slurry, keeping it wet or bagging it before disposal.
Water that is recycled on-site for use in water suppression should be effectively filtered to remove silica dust and prevent contaminated water continually passing through the system. Without an appropriate filtration system there is a risk that continual recycling of water will increase the concentration of silica dust in the water over time and subsequently the level of silica dust in the mist arising from the water suppression activities.
Water recycling systems can filter slurry so that silica and other dust particles are removed from the water before it is re-used. These systems can include:
Some products, such as commercially available flocculants, promote the clumping of particles, and will consolidate silica dust in recycled water more effectively. Water that is recycled needs to be visually assessed to ensure it is clear. If the water has a cloudy or milky appearance this means it is likely to contain a high concentration of silica dust and may increase the risk that airborne particles or contaminated mist will be released in the workplace.
For further information on the management of recycled water, please refer to guidelines in your state or territory.
The PCBU must ensure that containers of waste produced or generated at a workplace from a hazardous substance, including silica dust, are labelled. The label needs to reflect the nature of the waste as closely as possible, for example the label should identify the substance as ‘Silica dust hazard’.
Waste contaminated by silica dust can include any disposable clothing or PPE, rags used to clean the work area or tools or equipment that cannot be decontaminated or are no longer required.
Bags used for containing waste need to be strong enough to ensure they will not tear and release dust. To minimise the risk of a bag tearing or splitting, bags should not be filled more than half-full and excess air gently evacuated from the bag in a way that does not cause the release of dust.
The PCBU should have a waste management system in place that eliminates the risk of silica dust being released and becoming airborne.
Engineered stone that is already installed in the home or workplace is not a risk to health unless it is disturbed through mechanical processes such as cutting, sanding, grinding, drilling or polishing.
Workers undertaking maintenance or refurbishment of engineered stone using mechanical processes may be exposed to silica dust. This type of work should only be carried out by workers who have had suitable training.
The PCBU must manage risks to health and safety associated with the maintenance or refurbishment of engineered stone. One effective way to manage the risk is to conduct this work in a controlled exclusion zone with additional controls, as outlined in Part 4.4 of this Code.
When removing installed engineered stone in an area containing engineered stone, the PCBU should carefully plan before work commences so it can be carried out safely.
Planning involves identifying hazards, assessing risks and determining appropriate control measures in consultation with all persons involved in the work.
The PCBU must consider not only the direct hazards that are associated with this work, but also those hazards related to the work activity and work environment.
When undertaking removal work, a risk assessment is often the best way to determine the measures that should be implemented to control risks. Refer to Part 4 of this Code for information on how to manage and control the risks from working with engineered stone.
Key terms | Meaning | |
Crystalline silica | The crystalline form of the abundant naturally occurring mineral silica or silicon dioxide (SiO2). It is present in almost all types of rocks, sand, clays, shales and gravel and in construction materials such as concrete, tiles and bricks. | |
Duty holder | Any person who owes a work health and safety duty under the WHS Act including a person conducting a business or undertaking, a designer, manufacturer, importer, supplier, installer of products or plant used at work (upstream duty holder), officer or a worker. | |
Engineered stone | Engineered stone2 is an artificial product that:
Engineered stone does not include natural stone that has not been combined with other products or heat cured (for example granite and quartz in their natural state). 2 Engineered stone does not include concrete, concrete products, cement products, fibre cement, bricks, blocks, pavers, autoclaved aerated concrete, roof tiles, wall and floor tiles that are ceramic or porcelain, grout, mortar, render and plasterboard. | |
Workplace exposure standard | A workplace exposure standard published by Safe Work Australia in the Workplace Exposure Standards for Airborne Contaminants. | |
Hazard | A situation or thing that has the potential to harm a person. Hazards at work may include, noisy machinery, a moving forklift, chemicals, electricity, working at heights, a repetitive job, bullying and violence at the workplace. | |
Health and safety representative (HSR) | A worker who has been elected by their work group under the WHS Act to represent them on health and safety matters. | |
Ingress protection (IP) | The level of protection offered by an electrical enclosure or casing against the intrusion or accidental contact of solids and/or liquids. | |
May | ‘May’ indicates an optional course of action. | |
Must | ‘Must’ indicates a legal requirement exists that must be complied with. | |
Officer | An officer under the WHS Act includes:
A partner in a partnership or an elected member of a local authority is not an officer while acting in that capacity. | |
Person Conducting a Business or Undertaking (PCBU) | A PCBU is an umbrella concept which intends to capture all types of working arrangements or relationships. A PCBU includes a:
Individuals who are in a partnership that is conducting a business will individually and collectively be a PCBU. A volunteer association or elected members of a local authority will not be a PCBU. | |
Personal protective equipment (PPE) | Anything used or worn by a person to minimise risk to the person’s health and safety. | |
Required minimum protection factor | Minimum reduction in exposure required to reduce the wearer’s exposure below the workplace exposure standard. | |
Respirable crystalline silica (RCS) | Respirable dust (less than and equal to 10 micrometres (µm)) in diameter of the following CAS numbers:
Synonyms: α quartz, crystallized silicon dioxide, silica, calcined diatomaceous earth. | |
Respiratory protective equipment (RPE) | A type of PPE designed to protect the worker from inhaling an airborne hazardous substance. RPE includes masks and respirators. | |
Risk | The possibility harm (death, injury or illness) might occur when exposed to a hazard. | |
Should | ‘Should’ indicates a recommended course of action. | |
Worker | Any person who carries out work for a person conducting a business or undertaking, including work as an employee, contractor or subcontractor (or their employee), self-employed person, outworker, apprentice or trainee, work experience student, employee of a labour hire company placed with a 'host employer' or a volunteer. | |
Workplace | Any place where work is carried out for a business or undertaking and includes any place where a worker goes, or is likely to be, while at work. This may include offices, factories, shops, construction sites, vehicles, ships, aircraft or other mobile structures on land or water. | |
This template will help you to document the control measures used to manage the risks of exposure to respirable crystalline silica (silica dust) during the fabrication or processing of engineered stone products.