Abstract
Measurements of respirable dust (RD) and respirable crystalline silica (RCS) concentrations are reported for a range of activities, materials and workplaces in the construction industry. Some activities leading to high dust exposures are identified, such as work in confined spaces, the use of hand-held StihlTM saws and angle grinders without suppression or extraction, and dry sweeping and removal of rubble. RD and RCS concentrations are related to conditions on site including such factors as the softness, friability and silica content of the material; the weather conditions (dampness) and whether indoors or out; the proximity of the source of the dust to the worker’s breathing zone, and the use of water suppression or extraction and general ventilation.