Resources · Silica dust
Silica dust and the builders clean — what Queensland’s code actually says
The last dust on a build gets cleaned up after the saws have stopped, and a lot of it carries crystalline silica. There’s also a lot of half-right talk about what the rules require — a December 2026 vacuum deadline, a ban on brooms, a lower limit on the way. Here’s what the primary sources say, with links so you can check them.
The short version
The rules are older than the rumour, and the number isn’t moving
What the code says
Queensland has had a dedicated construction silica code of practice since 1 May 2023, and it covers clean-up and housekeeping — not just cutting and grinding. It tells businesses to clean silica-bearing dust with wet sweeping, low-pressure water or an M- or H-class vacuum, and lists dry sweeping, compressed air and high-pressure water as “not recommended”.
What 1 December 2026 changes
The name. Workplace Exposure Standards become Workplace Exposure Limits. Safe Work Australia has confirmed the silica figure isn’t changing on that date: it stays at 0.05 mg/m³ over an eight-hour day. There is no vacuum deadline in it anywhere.
Where the silica is
Why the final clean is a dust task, not just a tidy-up
Most of what a builders clean removes is residue from the materials Queensland’s code lists as containing crystalline silica: cement and concrete, mortar, grout, tiles, bricks and fibre-cement sheeting. Cut, ground or sanded, they leave a fine dust on every sill, track and floor. The code is explicit that the hazard doesn’t end when the tools stop — settled dust can be disturbed again, and it names dry sweeping and compressed air as the ways that happens.
Not all of it is silica. WorkSafe Queensland classes gypsum and plaster dust as general dust, so the white film from plasterboard sanding is a different material from the grey film off a tile saw. But on a finished site the two are mixed together and nobody can tell them apart by eye — which is the practical argument for cleaning all of it as though it carries silica. That last step is our reasoning, not a quote from the code.
Cleaning methods
What the code recommends — and what it doesn’t
| Method | The code’s position | Why |
|---|---|---|
| Wet sweeping | Safer | With enough water to keep the dust out of the air. |
| An M- or H-class vacuum | Safer | H-class where practicable; the code's controls table sets M or H as the minimum. |
| Low-pressure water | Safer | Dampens the dust instead of lifting it. |
| Dry sweeping | Not recommended | It disturbs settled dust and puts it back in the air. |
| Compressed air or blowers | Not recommended | The same problem, faster. |
| High-pressure water blasters | Not recommended | Listed with dry sweeping and compressed air as methods that can disturb the dust. |
“Not recommended” is the code’s wording, and it isn’t a ban. Where a safer method isn’t reasonably practicable, the code allows the others if the exposure is managed with respiratory protection for the people doing the cleaning and exclusion zones for everyone else. It also says cleaning should be done at least at the end of each day, so far as is reasonably practicable — dust that never builds up is dust nobody has to disturb later.
The code’s “should” carries more weight in Queensland than the word suggests. Its foreword sets out that a business must either comply with an approved code of practice or manage the risk in a different way that gives an equal or higher standard of safety.
Vacuum classes
L, M and H — and why HEPA isn’t one of them
| Class | Filtration | WorkSafe Queensland’s examples |
|---|---|---|
| L | 99% | Gypsum and plaster, general dust and dirt |
| M | 99.9% | Wood dusts such as MDF |
| H | 99.995% | Respirable crystalline silica, lead, asbestos |
The table is from WorkSafe Queensland’s guide to industrial vacuums for hazardous dusts, and the classes come from AS/NZS 60335.2.69. Two lines in that guide are worth reading twice. The first: “HEPA does not mean H-class.” The class is a rating of the whole machine, and WorkSafe says a domestic-rated vacuum, even one fitted with HEPA filtration, is neither guaranteed to provide a suitable level of protection nor designed for a commercial environment.
The second is about which class silica needs, and the guide says two things. Its table puts respirable crystalline silica in the H column; its note says both M- and H-class machines are accepted for construction dust containing silica. The code that came after it squares the two: H-class where it’s practicable, M-class where it isn’t, and M or H as the minimum in its controls table. What isn’t accepted is going lower — the same guide says inspectors will take enforcement action where substandard machines are used, “such as using an L-class machine to capture respirable crystalline silica dust”.
Half-right talk
Six things you’ll hear on site that the sources don’t say
“M- and H-class vacuums become mandatory in December 2026”
No such date exists. The M- and H-class wording has been in Queensland's construction silica code since it commenced on 1 May 2023. Nothing about vacuum class changes in December 2026.
“The silica exposure limit is being cut on 1 December 2026”
It isn't. On 1 December 2026 Australia's Workplace Exposure Standards become Workplace Exposure Limits. Safe Work Australia announced in June 2026 that there will be no changes to the limits for nine held-back substances, silica among them — it stays at 0.05 mg/m³ over an eight-hour day.
“Dry sweeping is banned in Queensland”
The code calls it “not recommended”, not prohibited. Where a safer method isn't reasonably practicable it can still be used — with respiratory protection for the people cleaning and an exclusion zone for everyone else.
“Queensland law requires an H-class vacuum”
The code accepts M or H for construction dust and prefers H where practicable. And it is the code that says so — the WHS Regulation itself doesn't mention vacuums at all.
“A HEPA filter makes a vacuum H-class”
WorkSafe Queensland's own words: “HEPA does not mean H-class.” The dust class is a rating of the whole machine under AS/NZS 60335.2.69, not of the filter inside it.
“All construction dust is silica dust”
WorkSafe Queensland files gypsum and plaster under general dust. The materials Queensland's code lists as containing silica include cement, concrete, mortar, grout, tiles, bricks and fibre-cement sheeting.
Who it applies to
Does any of this reach the cleaner?
Since 1 September 2024, Queensland’s regulation on processing crystalline silica substances has required that processing any material with at least 1% crystalline silica be controlled, in every industry. Whether a clean-up counts as “processing” is where the national and Queensland sources part ways. Safe Work Australia’s model code of practice lists “cleanup activities such as sweeping or vacuuming dust containing crystalline silica” as an example of processing, and names cleaners among the workers at risk of secondary exposure. That is Safe Work Australia’s reading in a model code — the Queensland material we read doesn’t give a clean-up example either way.
So the honest answer is that it depends on the site and on each business’s own risk assessment, and nothing here settles whether a particular final clean is construction work, or high risk. What the sources do agree on is the method: keep the dust out of the air. If you’re a builder or site manager working out what your subcontractors owe on a job, WorkSafe Queensland is the place to check.
What we do about it
We never dry-sweep construction dust — render and cement dust is the first thing off a site, and it doesn’t come off with a broom. P2 respirators (AS/NZS 1716) are worn while the dust is live. A SWMS for the clean, covering dust and silica, is available on request. The rest of the method is in our room-by-room builders clean checklist, and the stages it fits into are in rough, builders, sparkle and final cleans explained.
For a renovation that’s a post-renovation clean; for a build heading into practical completion it’s a handover and final clean. If you’re weighing up a general cleaner for the job, see builders clean vs bond clean.
FAQ
Common questions
Is dry sweeping construction dust illegal in Queensland?
No. Queensland's construction silica code lists dry sweeping as “not recommended” because it disturbs settled dust and puts it back in the air. Where a safer method isn't reasonably practicable, the code allows it if the exposure is managed with respiratory protection for the people cleaning and exclusion zones for other workers. The safer methods it names are wet sweeping, an M- or H-class vacuum, and low-pressure water.
Do I need an H-class vacuum for construction dust?
Queensland's code accepts either M or H class for construction dust containing silica, and says H-class should be used where it's practicable. WorkSafe Queensland's guidance on the code adds that a business choosing an M-class machine outside the code's controls table should be able to justify why H-class wasn't reasonably practicable. The classes come from AS/NZS 60335.2.69.
Does a HEPA filter make a vacuum H-class?
No. WorkSafe Queensland says it directly: “HEPA does not mean H-class.” L, M and H are ratings of the whole machine under AS/NZS 60335.2.69. WorkSafe also says a domestic-rated vacuum, even one fitted with HEPA filtration, isn't guaranteed to provide a suitable level of protection and isn't designed for a commercial environment.
What changes for silica on 1 December 2026?
The name of the limit, not the number. From 1 December 2026 Workplace Exposure Standards are replaced by Workplace Exposure Limits. Safe Work Australia announced in June 2026 that the limits for nine held-back substances, including respirable crystalline silica, will not change on that date — silica stays at 0.05 mg/m³ as an eight-hour time-weighted average. WorkSafe Queensland says a business's duty to manage exposure to airborne contaminants remains unchanged.
Is all construction dust silica dust?
No. WorkSafe Queensland classes gypsum and plaster dust as general dust. The materials Queensland's code lists as containing crystalline silica include cement, concrete, aggregates, fibre-cement sheeting, bricks, tiles, blocks, pavers, grout, mortar, sand and stone. On a finished site the two are mixed together, and nobody can tell them apart by eye.
Does the silica code apply to the cleaner doing the final clean?
The sources don't answer that in so many words. Queensland's code covers construction work and has a whole section on housekeeping and clean-up, but it doesn't mention cleaning contractors by name. Safe Work Australia's model code does: it lists cleanup activities such as sweeping or vacuuming silica-containing dust as an example of processing, and names cleaners among workers at risk of secondary exposure. How that lands on a particular job depends on the site and on each business's own risk assessment — WorkSafe Queensland is the place to check.
Sources
Everything on this page about what the rules say comes from WorkSafe Queensland and Safe Work Australia, accessed 21 September 2026. WorkSafe Queensland says its construction silica code is under review, so check the linked pages for the current version. This is general information, not work health and safety or legal advice.
- WorkSafe Queensland — Managing respirable crystalline silica dust exposure in construction Code of Practice 2022
- WorkSafe Queensland — Selecting the right industrial vacuum cleaner for hazardous dusts (PDF)
- WorkSafe Queensland — Regulation on processing crystalline silica substances
- WorkSafe Queensland — New workplace exposure limits (eSAFE, December 2025)
- Safe Work Australia — Model Code of Practice: Managing risks of respirable crystalline silica in the workplace
- Safe Work Australia — Workplace exposure limits for airborne contaminants
- Safe Work Australia — Decision on proposed exposure limits for 9 chemicals (June 2026)
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