Respirable crystalline silica (RCS) is released when cutting, grinding, or drilling concrete, brick, stone, tiles and mortar. It is small enough (PM4 and below) to reach deep into the lungs. The UK WEL for RCS is 0.1 mg/m³ (8-hr TWA) and controls must bring exposures below this.

Where exposure happens

• Dry cutting and chasing masonry
• Floor grinding and scabbling
• Drilling fixings in concrete or brick
• Mixing or dumping dry sand/cement

Short, intense bursts matter as much as long tasks—plumes can linger and spread across the work area without effective control.

Monitoring exposure

• Use personal sampling for formal assessments; it provides time-weighted data against the WEL.
• Use real-time particulate meters for spot checks and to optimise controls on the day.
• Log task, duration, controls used, and readings to guide improvements.

Controls that work

• Capture at source: water suppression, tool-mounted extraction, controlled feed speed.
• Capture in the air: LEV and H14-filtered air scrubbers or negative air units to cut background levels.
• Capture on surfaces: H-Class industrial vacuums; never dry sweep.
• RPE: P3/FFP3 with face-fit testing, worn correctly for the duration of exposure.

On larger rooms or multi-trade sites, portable units such as the MAXVAC Dustblocker can supplement tool extraction by managing the airborne fraction between tasks.

Legal responsibilities

• Conduct COSHH assessments and implement controls that achieve the WEL.
• Provide information, instruction and training; supervise use of controls.
• Maintain LEV and records; thorough examination and test at least every 14 months.
• Introduce health surveillance where risk warrants it.

Practical takeaways

• Plan for RCS: assume high risk on masonry work.
• Prioritise source capture and H14 final filtration for respirable fractions.
• Verify with sampling or spot monitoring and keep records.
• Fit-test RPE and check it daily; never rely on housekeeping alone.

RCS control is achievable with disciplined planning: capture at source, filter the air, clean with vacuums only, and verify the results.