Floor grinding, scarifying and surface preparation are among the highest-risk operations for Respirable Crystalline Silica (RCS) exposure on UK construction sites. Concrete floors contain 25–50% silica. Grinding generates a sustained cloud of RCS — concentrations that can exceed the Workplace Exposure Limit of 0.1mg/m³ many times over within seconds of starting without on-tool extraction.
HSE's 2026 enforcement programme targeted over 1,000 sites specifically for silica dust. Floor preparation work is within scope. The consequences are prohibition notices — work stops on the spot — and potential prosecution.
The COSHH requirement for floor grinding
Under COSHH 2002, wet suppression or on-tool extraction must be in place before dry grinding begins. For indoor floor grinding where wet suppression is impractical — polished concrete, resin floor preparation, grinding adjacent to structures that must stay dry — on-tool M-Class dust extraction is the compliant engineering control.
The extraction must be M-Class certified with the classification mark on the machine, connected directly to the grinder through its dust shroud, matched for airflow to the grinder manufacturer's specification, and documented in the COSHH assessment and method statement.
Why floor grinding is higher risk than cutting
Disc cutting and angle grinding generate RCS in bursts during active cutting. Floor grinding is continuous — the grinder is in contact with the silica-bearing surface for the entire duration of the operation, generating a continuous sustained dust cloud rather than an intermittent one. This means the extraction machine must handle higher sustained dust volumes than a machine used primarily for intermittent cutting operations.
The MIGHTY XL HSV 37L M-Class — with its larger tank, velocity monitor and automatic filter shaker — is the specification for sustained floor grinding operations. The velocity monitor confirms airflow is being maintained throughout the operation. The auto filter shaker prevents suction loss on long grinding runs.
Tile removal — check the adhesive first
Tile removal generates RCS from the tile and the substrate beneath, but also raises the question of the adhesive. Floor tiles laid before 1999 may have been bedded in asbestos-containing adhesive — a black bitumen-type adhesive is the most common form. Before any tile removal, a survey for asbestos-containing materials must be carried out. If ACMs are present in the adhesive, H-Class extraction is required and the work may require a licensed asbestos contractor.
Core drilling
Core drilling through concrete generates concentrated RCS at the drill bit. Power tool take-off (PTO) is the practical specification — the extractor starts automatically when the drill starts. The MIDI SYNCRO PTO H-Class is the specification for core drilling where H-Class is required, and the tufVAC M-Class PTO for standard concrete drilling.
- Floor grinding dust extraction — full guide →
- Silica dust control equipment →
- PTO dust extractors →
- M-Class extraction hub →
- HSE silica crackdown 2026 →
Always carry out a COSHH risk assessment before floor preparation work and check for asbestos-containing materials before tile removal.
