Monitoring air quaity on the Pilbara coast

The generation of dust and its impact on local communities remains a challenge for Rio Tinto Iron Ore ports at Dampier and Cape Lambert in the Pilbara region of Western Australia.

The Coastal Community Environmental Forum  provides an opportunity for discussion on community issues. It contains representatives from across a range of sectors in the community including local government and regulatory bodies.

Every year the Dampier Operations develop a Dust Suppression Improvement Plan which we submit to the Department of Environment, and we continue to implement capital and operational changes to reduce dust emissions in accordance with our Dampier Dust Management Plan.

We monitor air quality continuously at Dampier and at Karratha and new monitors have been installed at Wickham and King Bay. Dust levels can be monitoried by the public via a real-time online feed. A weekly summary of the Dampier PM10 data is published on this site every 12 hours. Dust is generally comprised of fine, airborne particles of earth or pollen material. Monitors used to measure dust may also measure smoke particles, salt, and other aerosols suspended in the air.

Dust monitoring instruments have a cut-off for the size range of the particulate matter they collect and measure. Particulate matter is commonly measured in three size ranges:

• Particulate matter with a diameter of less than 50 micrometres (also referred to as Total Suspended Particulates or TSP).
• Particulate matter with a diameter of less than 10 micrometres (or PM10).
• Particular matter less than 2.5 micrometres (or PM2.5).
   

These size ranges describe the diameter of the particles. For example, PM10 is used to describe particles with an aerodynamic diameter of less than 10 micrometres (1 thousandth of a millimetre).

Total suspended particulates are associated with nuisance dust or loss of amenity - this is visible dust. PM10 and PM2.5 are associated with the potential for health impacts, because particles below these sizes may penetrate the nose and enter the lungs. The concentrations of dust particles in the air are measured in micrograms per cubic metre of air (ug/m³).