Silica dust monitoring can feel overwhelming if you’re new to occupational hygiene or managing WHS at your workplace. Below, we’ve compiled the 20 most common questions we hear from Australian employers, safety managers, and contractors. These answers are grounded in current Australian WHS legislation, the AIOH Code of Practice, and Safe Work Australia guidance.
Frequently Asked Questions
Q: What is respirable crystalline silica (RCS)?
Respirable crystalline silica is a fine dust particle (typically less than 5 micrometres diameter) containing crystalline forms of silicon dioxide. It’s created whenever you cut, drill, grind, or demolish materials containing silica—concrete, stone, sandstone, granite, engineered stone, or silica-rich soils. When inhaled, these tiny particles penetrate deep into the lungs, potentially causing silicosis and other serious respiratory diseases. RCS is different from general dusts because of its crystalline structure and particle size.
Q: Who needs to conduct silica dust monitoring in Australia?
Any person conducting a business or undertaking (PCBU) that generates or exposes workers to respirable dust or RCS must monitor for it. This includes employers, contractors, sub-contractors, and even sole traders. If your work involves construction, demolition, mining, stone work, foundries, or similar high-risk activities, monitoring is a legal obligation under the Work Health and Safety Act 2011. Learn more about who must conduct silica monitoring.
Q: How often should silica monitoring be conducted?
There’s no one-size-fits-all answer. Frequency depends on your risk level, previous monitoring results, and whether your work processes have changed. High-risk operations with no monitoring history should start with baseline monitoring, then repeat every 3–6 months. Lower-risk operations with a stable history of results well below the exposure standard may only need monitoring every 2–3 years. Any change to work processes, tools, or controls triggers a re-assessment of frequency. See our detailed frequency guide.
Q: What is the silica exposure standard in Australia?
The WorkExposure Standard (WES) for respirable crystalline silica is 0.05 mg/m³ as an 8-hour time-weighted average (TWA). This has been in force since 1 September 2020. The WES for respirable dust (general, not specifically crystalline silica) is 1.5 mg/m³ TWA. In December 2026, a new Workplace Exposure Limit (WEL) framework will transition these standards. Understand the WES and upcoming WEL changes.
Q: How much does silica monitoring cost?
Costs vary based on the number of workers sampled, the type of monitoring (personal vs. static), whether you use a real-time monitor or gravimetric sampling, and your location. Expect $1,200–$3,500 per monitoring event for a typical small to medium construction or manufacturing site. Large operations or mining sites may pay more. Costs also depend on laboratory analysis fees (usually $150–$300 per sample for NATA-accredited analysis). Get a detailed cost breakdown.
Q: What’s the difference between personal and static air monitoring?
Personal monitoring measures the dust inhaled by a specific worker wearing a sampling pump and cassette on their lapel throughout a shift. It captures the actual exposure of that individual. Static monitoring (also called area monitoring) measures dust at a fixed location—such as near a workstation or at a site boundary—to assess the general air quality in a zone. Personal monitoring is more relevant for assessing compliance with the WES; static monitoring is useful for process control and identifying high-dust areas. Read our full comparison.
Q: What is a TWA (time-weighted average) result?
A TWA is the average concentration of dust measured over a full working shift (usually 8 hours). It accounts for fluctuations in dust levels throughout the day. The regulatory standard (0.05 mg/m³ RCS) is expressed as an 8-hour TWA. For example, if dust levels spike during grinding but are low for the rest of the shift, the TWA averages these variations. TWA results are compared directly to the WES to determine compliance.
Q: How long does a typical monitoring event take?
A single personal air sample usually runs for the duration of the worker’s shift—typically 6–8 hours. Static samples might run for 4–8 hours or longer, depending on the monitoring objective. The occupational hygienist visits your site, fits the sampling equipment, runs it during work, then removes it for laboratory analysis. From sample collection to final report, allow 2–3 weeks for NATA-accredited laboratory analysis and report generation.
Q: What happens if my monitoring results exceed the WES limit?
If results exceed 0.05 mg/m³ RCS, you must take urgent action: (1) notify affected workers and provide them with a copy of the result; (2) assess and upgrade control measures (engineering controls first—extraction, enclosure, or ventilation); (3) re-monitor within 1–3 months after controls are implemented; (4) review your work processes to identify the cause; (5) consider temporary RPE (respiratory protective equipment) if engineering controls are not immediately feasible. See what to do when exposure exceeds limits.
Q: Do I need NATA-accredited laboratory analysis?
Whilst not strictly mandatory by law, NATA accreditation for silica dust testing is industry best practice and strongly recommended. NATA-accredited laboratories meet rigorous quality standards and international protocols, ensuring your results are reliable and defensible. If you ever face a WHS investigation or litigation, NATA-accredited results carry significantly more weight. The additional cost is modest (typically $50–$100 per sample) compared to the assurance gained. Learn about NATA-accredited testing.
Q: What is health monitoring for silica exposure?
Health monitoring (or biological monitoring) involves medical surveillance of workers exposed to silica—typically baseline chest X-rays, lung function tests, and symptom questionnaires, sometimes repeated at intervals. It’s designed to detect early signs of silica-related disease before symptoms develop. Health monitoring is required for workers exposed above the WES or in certain high-risk industries (e.g., foundries). It differs from air monitoring: air monitoring measures the dust in the workplace; health monitoring measures the effect on workers’ health. Explore air monitoring vs. health monitoring.
Q: Do sole traders need to conduct silica monitoring?
Yes. Under the WHS Act, sole traders are PCBUs and must comply with all WHS obligations, including dust monitoring if they generate or expose workers (including themselves or employees) to respirable dust or RCS. A sole trader conducting silica-generating work has the same legal duty to monitor as a large construction company. This is one of the most misunderstood areas of WHS compliance among small operators.
Q: What industries are at highest risk of silica exposure?
High-risk industries include construction and demolition (concrete cutting, grinding, drilling), stone working (fabrication, cutting, polishing), mining and quarrying, foundries, sandblasting, tunnelling, and brick/tile manufacturing. Agriculture and rural industries are often overlooked but carry risk from siliceous soil dust, grain handling, and on-farm construction. See the full list of at-risk industries.
Q: What changes with the December 2026 WEL transition?
In December 2026, Australia transitions from the WorkExposure Standard (WES) to a new Workplace Exposure Limit (WEL) framework. For RCS, there is expected to be minimal change to the 0.05 mg/m³ limit itself, but the framework and compliance approach will evolve. New guidance and assessment methods may be introduced. Employers should begin preparing now to ensure a smooth transition and avoid compliance gaps. Prepare for the WEL transition.
Q: Can I use a real-time dust monitor instead of gravimetric sampling?
Real-time monitors are excellent for process control and identifying high-dust activities, but they cannot replace gravimetric sampling for formal compliance assessment. Real-time monitors give instant readings but lack the precision and reliability of gravimetric sampling (where dust is collected on a filter and weighed in a laboratory). For legal compliance and reporting to regulators, gravimetric sampling with NATA analysis is essential. You may use real-time monitors as a supporting tool. Compare real-time and gravimetric methods.
Q: How long must I keep dust monitoring records?
You must retain all air monitoring records for at least 30 years. This applies to both personal and static sampling data, laboratory reports, and copies of results provided to workers. The 30-year requirement reflects the latency period of silica-related diseases—symptoms may not appear for decades. Proper record-keeping also protects you in the event of a WHS investigation or worker compensation claim.
Q: What is the engineered stone ban and how does it affect my monitoring obligations?
Engineered stone products (typically 90%+ crystalline silica content) have been progressively banned in Australia due to the epidemic of accelerated silicosis among fabricators. Victoria’s ban took effect July 2024; other states are implementing similar measures. If you previously worked with engineered stone or are now using natural stone alternatives (granite, quartzite, or porcelain), your monitoring obligations remain the same—continue to monitor and control silica exposure. Understand the engineered stone ban and your options.
Q: What should I look for when choosing an occupational hygienist?
Look for credentials: AIOH membership, tertiary qualifications in occupational hygiene, and professional indemnity insurance. Ensure they understand your specific industry and have recent experience in your field. They should have relationships with NATA-accredited laboratories and be able to design tailored monitoring programs (not one-size-fits-all). Ask for references from similar operations and confirm they’ll provide written reports and support you in interpreting results. Learn how to choose the right hygienist.
Q: What is silicosis and can it be prevented?
Silicosis is a chronic lung disease caused by inhaling respirable crystalline silica dust over time. There is no cure, but it is entirely preventable through effective dust control and monitoring. The disease progresses through exposure; workers with a history of high exposure are at greater risk. Prevention relies on hierarchy of controls: (1) eliminate or substitute high-silica materials where possible; (2) engineer controls (local exhaust ventilation, wet suppression, enclosure); (3) administrative controls (job rotation, break schedules); (4) RPE as a last resort. Explore silicosis prevention and employer obligations.
Q: What is the difference between WES and WEL?
The WorkExposure Standard (WES) is the current regulatory exposure limit for hazardous substances, introduced in 2001. The Workplace Exposure Limit (WEL) is a new framework being rolled out nationally from December 2026, replacing the WES. The WEL is intended to harmonise exposure limits across states, improve transparency, and align with international standards. For RCS, the numerical limit is not expected to change significantly, but the framework and compliance methods may evolve. Understand WES vs. WEL.
Can’t Find Your Answer?
If your question isn’t covered here, our occupational hygienists are ready to help. Whether you’re designing a monitoring program, interpreting results, or preparing for the WEL transition, contact Anitech Group for expert guidance tailored to your industry and workplace.
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- FEATURE: 1200x630px. A diverse team of safety managers and occupational hygienists reviewing silica monitoring data on tablets and documents at a construction site planning table; professional, collaborative atmosphere; Australian workplace setting visible in background.
- BODY_1: 800x450px. Close-up of a personal air sampling cassette being attached to a worker’s lapel during setup; hygienist’s gloved hands visible; shows the practical “how-to” of personal monitoring after the “Personal vs Static Monitoring” section.
