Stone, Silica and Worktop Fabrication

Engineered stone can contain up to about 95% crystalline silica. Granite is typically around 25 to 40%, sandstone can exceed 70%, and limestone and marble are usually low but supplier-data-dependent. The same cut on engineered stone produces far more of the dangerous dust.

HSE EH40

0.1 mg/m³ respirable crystalline silica as an 8-hour time-weighted average. Minutes of dry cutting engineered stone can exceed it many times over.

Water suppression must reach the point of cut through an on-tool feed at the correct flow, running for the whole cut including the start and finish. On-tool extraction must use the shroud designed for that tool and disc size, M class minimum for silica, H class better.

Dry fabrication typically gives five to ten times higher respirable crystalline silica exposure than wet methods using the same tools. Dry cutting of engineered stone must stop.

Local exhaust ventilation must be thoroughly examined by a competent person at least every 14 months, with records kept.

RPE is the last line of control, used for the residual exposure after water, extraction and enclosure have done their work. Every wearer of tight-fitting RPE must be face-fit tested for the specific make, model and size, and retested if the wearer's face changes significantly or the make or model changes. Facial hair at the seal defeats the mask, so a worker who will not be clean shaven needs a powered hood or visor instead.

Baseline and periodic respiratory questionnaire and spirometry, with chest imaging where indicated and an exit assessment, required where exposure is significant. Individual health records must be kept for at least 40 years from the last entry.

HSE is running a programme of more than 1,000 fabricator inspections across Great Britain through 2026/27, and has already ordered some fabricators to stop working with engineered stone where workers were not protected from silica dust.