The effects of respirable Silica dust and strategies to minimise dust emissions

Occupational health and safety legislation states that workers must not be exposed to Respirable Crystalline Silica (RCS) levels above the national exposure standard of 0.05 mg/m3 (in an 8 hour Time Weighted Average period).

Regulations require that exposure to hazardous substances be prevented where practical. If exposure can’t be prevented, the risk must be reduced firstly by controls other than personal protective equipment (PPE). PPE should only be used to manage any remaining risk.


Silica is a natural mineral which is found in rocks, sand and clay. It is thus found in bricks and concrete too. A small fraction of Silica occurs in a sharp, hard crystalline form. Particles smaller than 10 microns in diameter can be breathed directly into the lungs and can cause damage leading to Silicosis. This is called ‘Respirable Crystalline Silica’ or RCS. 

Manage dust using control systems

Using local extraction ventilation, either fixed or on-tool

  • Shadow vacuuming
  • Vacuum clean-up rather than sweeping
  • Not blowing dust with compressed air

Manage dust by switching methods

Manage dust by elimination

Use cast-in channel systems for anchor points for brackets instead of post-installed options