The reasons for suppressing dust are numerous and vary for particular industries; however, the main points are:
Loss of valuable material
Up to 5% of finished products can be lost due to wind erosion from stockpiles alone.
Dust can contaminate the atmosphere, surrounding areas and local villages. It can also enter the food chain by polluting potable water sources and the soil.
Dust is responsible for certain diseases including silicosis and pneumoconiosis (black lung disease).
Atmospheric pollution can cause hazardous working conditions for vehicle drivers and plant operators.
Very fine (10 - 20 micrometres) combustible particles constitute a high explosion risk. Coal stockpiles can also oxidise and develop "hot spots" if not capped by chemical film formers.
Dust particles can contaminate machinery such as bearings, air filters and various engine parts.