This leaflet has been produced by HSE and the Highways Agency. It is aimed at workers in highway paving construction or maintenance work. Workers who use a cut-off saw (also known as a disc cutter, a con saw or a 'whizzer') while cutting kerbs, paving or blocks can produce enormous amounts of dust. The dust will contain some very fine dust called respirable crystalline silica (RCS). Exposure to RCS dust can cause serious health problems. The leaflet explains how RCS dust exposure can affect health and what to do to control the risks.