Why Australian silica law tightened so sharply
Australia has spent the past decade responding to a resurgence of silicosis, an irreversible and sometimes fatal lung disease caused by inhaling respirable crystalline silica. The trigger was a wave of accelerated silicosis among engineered stone workers, but the regulatory response has deliberately reached much wider than that industry.
Two things followed. The engineered stone benchtop, panel and slab trade was prohibited outright from 1 July 2024, with imports prohibited from 1 January 2025. And separately — the part that catches many businesses by surprise — the processing of all crystalline silica substances came under stronger regulation from 1 September 2024, across every industry.
If you buy, store, handle or process silica sand or quartz powder in Australia, the second change is the one that applies to you.
The abrasive blasting prohibition
This is the clearest rule and the one most often broken through simple ignorance.
The reason is mechanical. Blasting drives grains against a hard surface at high velocity, shattering them and generating enormous quantities of fine, freshly fractured particles — exactly the respirable fraction that reaches the deep lung, and freshly fractured silica surfaces are more biologically reactive than aged ones. Few industrial activities generate RCS as efficiently.
Compliant alternatives are well established: garnet, slag-based abrasives, engineered and recycled media. Suppliers of these publish free-silica content, and the reference points used in the trade are ISO 11126-10 and SSPC-AB1.
PIME will not supply silica sand as a blasting medium for use in Australia. It is a use we decline rather than a use we price.
The 2024 crystalline silica substance rules
From 1 September 2024, following national agreement, the model WHS Regulations were amended to control the processing of crystalline silica substances across all industries.
What counts as a CSS: any material containing at least 1% crystalline silica by weight. That is a low bar and a wide net — bricks, blocks, pavers, tiles, mortar, concrete and cement-based products including fibre-cement and AAC, and also rocks, sand and clay. Silica sand and quartz powder are at the far end of the range.
What counts as processing: cutting, sawing, grinding, drilling, polishing, scabbling and crushing — the activities that liberate dust from a solid or bulk material.
What is required:
- Before starting, assess whether the processing is high risk.
- Where it is high risk, apply additional control measures and prepare a written silica risk control plan.
- Maintain controls, and support them with air monitoring and health monitoring where the framework requires it.
The critical change is the breadth. These duties are not confined to construction or stonemasonry. A foundry, a ceramics plant, a paint factory, a filtration media supplier or a laboratory handling bulk silica all fall within scope if they process a CSS.
The exposure standard, and what it is not
The workplace exposure standard for respirable crystalline silica in Australia is 0.05 mg/m³ as an eight-hour time-weighted average, halved from the earlier 0.1 mg/m³. Compliance is required under Commonwealth, state and territory WHS law.
It is worth being clear about what a WES is. It is a legal maximum, not a safe threshold. The WHS framework requires exposure to be eliminated or minimised so far as is reasonably practicable — being under the number is the floor of compliance, not the goal. In practice that means the ordinary hierarchy of control: substitute where you can, enclose and automate, apply local exhaust ventilation and water suppression, and treat respiratory protective equipment as the last layer rather than the first.
What this means if you buy silica sand
Five practical implications:
- Know your crystalline silica content and have it documented. Your risk assessment depends on it. Ask your supplier for the figure, and for a current SDS.
- Assess before you process, not after. The high-risk assessment is a precondition of starting work, and a control plan written after an incident is not compliance.
- Do not buy silica sand for blasting. If a supplier offers it for that purpose in Australia, that tells you something useful about the supplier.
- Wet methods and enclosure beat PPE. Water suppression and extraction at the point of generation are far more effective than respirators, and regulators expect to see them.
- Consider whether you need a dry process at all. Substitution sits at the top of the hierarchy for a reason, and it is the control most often skipped over.
None of this makes silica sand difficult to buy or use — it remains one of the most widely used industrial minerals in the country, in water treatment, foundries, glass and construction. It does mean the material arrives with duties attached, and a supplier who hands over the documentation without being chased is worth more than one who does not.
PIME supplies a current SDS with every consignment and will provide crystalline silica content data for your risk assessment. Our guide to silica sand grades covers how to specify the material itself.
Frequently asked questions
Is it legal to use silica sand for sandblasting in Australia?
No. Australian work health and safety law prohibits abrasive blasting using a medium that contains more than 1% crystalline silica. Silica sand is effectively pure crystalline silica, so it falls far outside that limit — as do river sand, beach sand and other natural white sands. The prohibition exists because blasting shatters grains and generates extremely high airborne concentrations of respirable crystalline silica. Compliant alternatives include garnet, slag abrasives and engineered media.
What is a crystalline silica substance under the 2024 regulations?
A crystalline silica substance, or CSS, is defined as any material containing at least one per cent crystalline silica by weight. That captures a very wide range of materials: bricks, blocks, pavers, tiles, mortar, concrete and cement products including fibre-cement sheeting and autoclaved aerated concrete, plus rocks, sand and clay. Silica sand and quartz powder sit at the extreme end of that definition.
What must a business do before processing a crystalline silica substance?
Since 1 September 2024, a business must assess whether the processing will be high risk before it starts. Processing means cutting, sawing, grinding, drilling, polishing, scabbling or crushing — anything that can liberate dust. Where the processing is assessed as high risk, additional control measures are required together with a written silica risk control plan. This applies across all industries, not only construction, which is the change many businesses missed.
What is the workplace exposure standard for respirable crystalline silica?
The workplace exposure standard is 0.05 mg/m³ as an eight-hour time-weighted average. It was halved from the previous 0.1 mg/m³ figure, and compliance is required under Commonwealth, state and territory WHS laws. It is a legal maximum rather than a safe level, and the expectation under the WHS framework is that exposure is reduced so far as is reasonably practicable below it, not merely kept under the number.