Refocus on Safety – RCS

26 Aug 2020

John Egan, Safety & Training Services Executive, speaks about RCS management.

As part of the CIF’s Refocus on Safety campaign, the focus for week commencing 24th August is on Respirable Crystalline Silica (RCS).

HILTI has kindly facilitated a brief video to advise of the engineering controls available to effectively  eliminate the presence of airborne RCS dust; this may be accessed here:

Dave O’Duffy, HILTI elaborates on the appropriate controls, in advising that “Effective dust removal works as a system, you need quality inserts that go into the tools like drill bits or diamond blades, you need a power tool with optimised airflow, plus a dust removal module to go on the tool and you need M or H class vacuum. This will reduce the RCS dust by 99.8% on a typical application”.


Crystalline silica is a naturally occurring substance typically found in stone (particularly sandstone, shale, granite, and slate), in the sand and in products such as bricks, tiles, concrete and cement. Refer to Table 1.


Respirable Crystalline Silica (RCS) occurs when these materials are worked on to release a very fine, inhalable dust. Where concrete, stone or sand-based materials are altered (during formation, cutting, drilling, polishing or demolition) and made airborne, there is a potential for exposure to crystalline silica dust.


Inhalation is the primary route of exposure to crystalline silica dust. When any dust is inhaled, its point of deposition within the respiratory system is very much dependent upon the range of particle sizes present in the dust. The respirable fraction (smallest particle size) of crystalline silica dust can penetrate deep into the lungs.

The EU’s Carcinogens and Mutagens Directive has been updated and has classified Respirable Crystalline Silica (RCS) as a category 1 carcinogen; this came into effect in EU member states as of 17th January 2020. The Occupational Exposure Limit Value (OELV) established for Silica, both crystalline and respirable, over an 8-hour reference period is 0.1 mg/m3. This is clearly defined under the Health and Safety Authority’s Chemical Agents Code of Practice 2020

How to Manage RCS

The respirable fraction of the dust is invisibly fine. Elimination and substitution of RCS containing materials, dust extraction and/or dust suppression are the primary measures advised to control potential exposure.

Always assume that exposure is likely to occur and protect according to the level of risk identified from risk assessment. In summary:

  • Prepare written risk assessments (required by law) highlighting the key hazards, risks, and controls in place.
  • Use safe systems of work to reduce exposure based on the risk assessment.
  • Use dust suppression techniques during work.
  • Use of engineering controls such as local exhaust ventilation to control exposure can be very effective.
  • Use and store personal protective equipment according to instructions to reduce exposure.

Further Information

Additionally, Michael O’Connor, Group EHS Director, Mercury has shared a video on behavioural safety, which may be viewed here:

CIF –     

HSA CoP –     Chemical Agents Code of Practice 2020

HSA Info. –    Crystalline Silica Dust Information Sheet

EU-OSHA –   Addressing Risks from Worker Exposure to RCS

IOSH –           Silica Fast Facts Infographics

BOHS –          Breathe Freely

Please use #CIFSITESAFETY to highlight your safety initiatives on social media and the CIF will endeavour to provide support.

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