Concrete Grinding & Polishing Silica SWMS

Concrete grinding and polishing abrades the surface of concrete, terrazzo and masonry floors with diamond grinding heads, cup wheels and polishing pads, and the abrasion liberates respirable crystalline silica (RCS) from material that is commonly 20 to 40 per cent crystalline silica by mass. Grinding is a particularly insidious silica task because it is often carried out indoors, over large floor areas, and for sustained periods, so RCS can accumulate in an enclosed space and reach high concentrations even where each individual pass seems light. Dry grinding without extraction is one of the highest-exposure activities in the finishing trades, and the model Work Health and Safety Regulations treat this work as processing of a crystalline silica substance with a dedicated high-risk regime, not as ordinary floor preparation.

The controlling number is the workplace exposure standard for RCS: 0.05 mg/m3 as an eight-hour time-weighted average, which must not be exceeded, and which is reframed as a workplace exposure limit from 1 December 2026. Processing of a crystalline silica substance — which includes grinding and polishing concrete — is high risk where it is reasonably likely to result in a risk to health, the practical trigger being airborne RCS above half the exposure standard generated on a regular basis. Sustained floor grinding readily reaches that threshold, which triggers the duty to prepare a silica risk control plan, train exposed workers, conduct air monitoring, and provide health monitoring through a registered medical practitioner. The dominant engineering control is on-tool dust extraction through an H-class (HEPA) vacuum matched to the grinder, or a wet grinding process where the floor system allows; this document is written on the basis that dry grinding without extraction will breach the standard and must be eliminated wherever practicable.

Hazards identified

10 hazards covered, sorted by priority.

Control measures

Hierarchy-of-controls order: elimination → substitution → isolation → engineering → administrative → PPE.

1. 1Elimination: where a floor finish allows, specify a system that does not require extensive on-site grinding, removing part of the silica-generating task.
2. 2Substitution: select a wet grinding and polishing process over dry grinding where the floor system permits, as wet processing sharply reduces airborne RCS.
3. 3Engineering: on-tool dust extraction through an H-class (HEPA) vacuum correctly matched to the grinder as the primary control for dry grinding, maintained so the shroud seal and filter perform, keeping airborne RCS below the exposure standard.
4. 4Engineering: where wet grinding is used, manage slurry at the point of generation and protect the supply with residual current device protection because water and power are present together.
5. 5Administrative: assess the task for silica risk and, where sustained grinding makes it high-risk processing of a crystalline silica substance, prepare a silica risk control plan before the work starts and arrange air monitoring to confirm the controls hold below the exposure standard.
6. 6Administrative: enrol workers carrying out high-risk silica work in health monitoring supervised by a registered medical practitioner, including respiratory function testing and low-dose high-resolution chest CT, and retain records confidentially for at least 30 years.
7. 7Administrative: isolate the grinding area from other trades and occupants, control access, sequence the work so following trades do not enter until the area is decontaminated, and rotate operators to limit exposure and vibration dose.
8. 8Administrative: follow the safety data sheets for densifiers, sealers and polishing compounds, providing ventilation and skin and respiratory protection for surface-chemical application.
9. 9PPE: a fit-tested P2 half-face respirator as the minimum residual control, upgraded to a powered air-purifying respirator for extended or higher-exposure grinding, selected and maintained per AS/NZS 1715 and AS/NZS 1716.
10. 10PPE: hearing protection matched to the measured noise level, eye protection to AS/NZS 1337.1, gloves, and Class I or Class II safety footwear with protective toecap to AS/NZS 2210.3.
11. 11Administrative: all workers must hold a valid White Card (General Construction Induction Training, CPCCWHS1001) before entering any construction workplace.
12. 12Administrative: conduct a daily pre-start toolbox talk covering the grinding scope, dust extraction, area isolation, surface chemicals and required PPE, and record attendance in the SWMS consultation section.
13. 13Administrative: clean up with an H-class vacuum or wet methods only — never dry sweep or use compressed air, which re-suspends settled RCS — and contain slurry so it does not enter stormwater.
14. 14Administrative: review and update this SWMS whenever the work scope changes, after any incident or near miss, when a worker or health and safety representative raises a concern, when new hazards are identified, or at minimum every 12 months.

Applicable Codes of Practice

High-Risk Silica Work triggered

Worked example

A polished concrete contractor is engaged to grind and polish a large open-plan retail floor across several stages, from coarse diamond grinding through to fine polishing. Because the grinding runs over a large indoor area across several shifts, the supervisor assesses it as high-risk processing of a crystalline silica substance, prepares a silica risk control plan, and books air monitoring on a representative shift to confirm the controls hold below the exposure standard. Each walk-behind grinder is fitted with a shroud connected to an H-class vacuum sized to the machine, and the shroud seals and filters are checked before each shift so extraction performs. The grinding zone is isolated from the rest of the site with the area sealed off, and following trades are kept out until the floor and surfaces have been decontaminated. Operators wear fit-tested P2 respirators, moving to powered air-purifying respirators for the sustained coarse grinding, along with hearing and eye protection, and are rotated through the day to limit exposure and vibration. The densifier and sealer are applied per their safety data sheets with ventilation. At the end of each shift the floor and surfaces are cleaned with the H-class vacuum rather than swept. Personal monitoring returns a result below the exposure standard, the result and worker training are recorded, and the operators are enrolled in health monitoring with a registered medical practitioner.

Related legislation

• Model Work Health and Safety Act — primary duty of care; the duty to consult workers; the reckless-conduct offence; and notifiable-incident provisions, as enacted in each jurisdiction.
• Model Work Health and Safety Regulations — the crystalline silica provisions governing processing of a crystalline silica substance, the high-risk processing definition, the silica risk control plan, training, air monitoring and health monitoring, as enacted in each jurisdiction.
• Workplace exposure standard for respirable crystalline silica: 0.05 mg/m3 (eight-hour time-weighted average), which must not be exceeded; reframed as a workplace exposure limit from 1 December 2026.
• From 1 September 2024, stronger regulation of work with all materials containing at least 1 per cent crystalline silica across all industries.
• Victoria operates under the Occupational Health and Safety Act 2004 and the Occupational Health and Safety Regulations 2017, with the silica provisions and Compliance Codes applying in place of the model instruments.

Frequently asked questions