Silica Dust Control for Engineered Stone and Stone Cutting Work
Engineered Stone Dust in Brief
- Dry cutting of engineered stone is no longer an acceptable way of working
- Water suppression on the tool plus powered respiratory protection
- Health surveillance for anyone regularly exposed to silica dust
Engineered Stone and Silica Dust
Engineered stone, sometimes called quartz composite or agglomerated stone, is the material behind most modern kitchen and bathroom worktops. It is made by binding crushed quartz in resin, and the finished slabs can contain up to 95 per cent crystalline silica. By comparison, granite typically contains between 20 and 45 per cent, and marble far less. When engineered stone is cut, ground, drilled or polished, the crystalline silica is released as respirable crystalline silica (RCS) - dust particles so fine they are invisible in normal light and penetrate deep into the lungs.
RCS exposure causes silicosis, chronic obstructive pulmonary disease and lung cancer. What sets engineered stone apart is the speed of harm. Cases of accelerated silicosis have been diagnosed in worktop fabricators after months or a few years of exposure, not the decades traditionally associated with the disease. Many of those affected are young workers, and silicosis is incurable and often progresses even after exposure stops.
In the UK, the workplace exposure limit for RCS is 0.1 mg/m3 as an 8-hour time-weighted average, but the legal duty under COSHH goes further than staying under a number: exposure must be reduced to as low a level as is reasonably practicable. Dry processing of engineered stone produces RCS exposures around 5 to 10 times higher than wet methods, which is why the way the material is worked matters so much.
The 2026 HSE Guidance on Engineered Stone
In May 2026, the UK's Health and Safety Executive (HSE) published its first COSHH guidance written specifically for engineered stone, stating plainly that dry cutting and dry processing of the material is not an acceptable way of working. The guidance is not new law and does not amount to a formal ban - it clarifies how the existing duties under COSHH apply to this material. In practice, the effect is much the same: an inspector finding dry processing will treat it as a failure to adequately control exposure, with enforcement action to match.
The guidance arrived ahead of a national inspection programme. HSE plans more than 1,000 inspections of worktop fabricators and stone processors through 2026 and 2027, focusing on how silica dust exposure is controlled. Businesses that fabricate, cut or fit engineered stone should expect a visit and should be able to show their controls working, not just written down.
The guidance also highlights product choice. Lower-silica engineered stone is now available at comparable quality and price, and choosing it is a control measure in its own right - the less silica in the slab, the less RCS in the dust.
Controlling Silica Dust When Cutting Engineered Stone
Control starts before any blade touches the slab. Specifying a lower-silica material removes hazard at source. Accurate templating means worktops arrive at the customer's property finished and ready to fit, so cutting on site - the hardest environment in which to control dust - is eliminated rather than managed.
Where cutting, grinding and polishing does take place, water is the primary control. On-tool water suppression keeps dust out of the air at the point it is created, whether on a bridge saw, a CNC machine or a hand-held polisher. The mist thrown up by wet processing needs controlling too, because it carries silica with it - good workshop ventilation or mist extraction deals with what the water alone cannot.
Housekeeping follows the same logic. Slurry dries into fine dust that becomes airborne again the moment it is disturbed, so cleaning is by wet methods or a suitable extraction unit, never dry sweeping and never compressed air. Access to processing areas is restricted to those who need to be there, and work clothing should be non-dust-retaining coveralls laundered by a contract service rather than taken home.
Companies can ensure safety when cutting engineered stone such as having a saw which feeds water straight to the blade and the mist extraction runs whenever the saw does. This can ensure nothing dry touches engineered stone, which is what poses significant risks.
Templating can also greatly improve safety. A digital templater can reduce site cutting where it is hard to reduce risks. Washing down at the end of every shift is also important, because dried slurry is just dust waiting to happen.
Respiratory Protection for Engineered Stone Work
Even with wet methods and extraction in place, respiratory protective equipment (RPE) is still needed for processing, cleaning and machinery maintenance. For engineered stone the expectation has moved beyond the disposable FFP3 (Filtering Facepiece 3) mask. Powered air purifying respirators (PAPR) with an assigned protection factor (APF) of at least 20 are the baseline, with APF 40 preferred for processing work.
There are practical reasons for this. A tight-fitting mask only achieves its protection factor with a good face seal, which demands face fit testing, a clean-shaven face and disciplined wear over long, hot, physical tasks - conditions that rarely all hold at once. A powered respirator does not rely on negative pressure, is more comfortable over a full shift, and keeps protecting when the wearer is breathing hard. Where tight-fitting RPE is used for any silica work, face fit testing for each wearer remains essential, and all RPE needs storing, checking and maintaining properly.
The mistake I see most often is treating the mask as the control. RPE is the last line of defence under COSHH, not the first - if someone is relying on a disposable mask to work engineered stone dry, both parts of that sentence are a problem.
The other gap is assuming a fitted FFP3 covers everything. For this material the guidance points firmly at powered respirators, and once you cost in fit testing, wastage and lost productivity from mask breaks, a decent PAPR unit is not the expensive option people assume.
And do not forget the person cleaning the workshop at the end of the day. They are often the most exposed and the least protected.
Health Surveillance for Silica Dust Exposure
Anyone regularly exposed to RCS should be under respiratory health surveillance. For silica this typically involves a respiratory questionnaire and lung function testing at set intervals, with referral for further assessment where results indicate it. Surveillance serves two purposes: it can pick up disease early enough to act, and a pattern of results across a workforce tells you whether the controls are actually working.
Training completes the picture. Workers need to understand what RCS does, why dry methods are prohibited on engineered stone, how to use and look after their RPE, and what the health surveillance programme is for. Records of exposure assessment, RPE issue and maintenance, training and health surveillance are the evidence that the whole system exists in practice.
When auditing a stone fabricator I want to see a COSHH assessment that names engineered stone specifically, not a generic dust assessment. Then I follow the trail: RPE issue and maintenance records, face fit or PAPR checks, health surveillance records, and a walk through the workshop to confirm the wet methods described on paper are the ones in use at the saw.
Practical Compliance Guidance
Hazardous substances including silica dust are managed within the hazard identification, COSHH and operational control arrangements in the IMS1 Manual. For organisations that fabricate, cut or fit stone, a set of documents specific to the material can sit alongside a wider health and safety system.
The following alphaZ documents provide the specific assessments and PPE records needed for stone processing and fitting work.
| alphaZ document | How to use it |
|---|---|
| COSHH-97 Engineered Stone Dust | A pre-prepared COSHH assessment for engineered stone dust, covering the RCS hazard, wet processing controls, RPE and health surveillance. |
| COSHH-71 Granite Dust | A pre-prepared COSHH assessment for natural stone and granite dust, for organisations working stone with lower but still hazardous silica content. |
| RA-HS156 Engineered Stone Worktop Fabrication and Fitting | Risk assessment for engineered stone worktop work, covering workshop fabrication, on-site fitting, cleaning and slurry, slab handling and machine hazards. |
| RA-HS97 Ceramic and Stone Tile Fixing | Risk assessment for tile fixing work, distinguishing the controls for ceramic and porcelain from the stricter requirements for engineered stone. |
| RA-HS27 Cutting Abrasive Wheels | Risk assessment for the use of cutting wheels, abrasive discs and grinding cutters, tools and activities which may be involved in cutting stone. |
| PP-7-01 Safe Use and Management of PPE Policy Procedure | Policy and procedure for the selection, issue, use and maintenance of personal protective equipment including RPE. |
| F-HS2 Employee PPE Issue Sheet | Record of PPE and RPE issued to each worker, providing the evidence trail for what protection was provided and when. |
Note - all the above files can be downloaded with an alphaZ subscription.
Frequently Asked Questions
UK Legislation
The following UK legislation is directly relevant to silica dust and stone processing. Organisations outside the UK should identify the equivalent legislation applicable in their jurisdiction.
- Control of Substances Hazardous to Health Regulations 2002
- Health and Safety at Work etc. Act 1974
- Management of Health and Safety at Work Regulations 1999
- Provision and Use of Work Equipment Regulations 1998
- Personal Protective Equipment at Work Regulations 1992
