Respirable crystalline silica

RCS

The fine dust released when concrete, stone, brick, mortar and tile are cut, drilled or ground, which causes silicosis and lung cancer and is strictly limited under COSHH.

Crystalline silica is in most of the materials a construction site cuts. When it is released as respirable dust (particles small enough to reach the deep lung), it causes silicosis, an incurable scarring of the lung, and is a recognised cause of lung cancer and COPD. The HSE estimates hundreds of construction deaths a year from past exposure. The workplace exposure limit is very low, and a single shift of dry cutting concrete with an angle grinder and no control can exceed it many times over.

The control hierarchy is specific: avoid generating the dust (pre-cut off site, use block splitters, design out chasing); control at source with water suppression or on-tool extraction (M-class or better); then respiratory protection as the last layer, face-fit tested, with an assigned protection factor of at least 20 for most cutting tasks (an FFP3 disposable or a half mask with P3 filters). Health surveillance is required for workers regularly exposed. The HSE runs periodic inspection campaigns on dust in construction and treats uncontrolled dry cutting as a serious matter.

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