Particle pollution is a mixture of solid particles and liquid droplets. EPA Victoria monitors the air for two categories of particle size: PM2.5 and PM10. These particles are very small and are measured in micrometres (µm).
PM10 particles (often described as coarse particles) are smaller than 10 micrometres (0.01 mm) in diameter.
The PM10 data on our website is reported as a mass per volume of air – micrograms per cubic metre (µg/m3). At some air monitoring stations we also measure particles by the visibility reduction they cause.
Health effects of PM10 particles
High levels of PM10 particles in the air can irritate the eyes and throat. People with existing heart or lung conditions (including asthma) can experience an increase in symptoms, including wheezing, chest tightness and difficulty breathing.
Sources of PM10 particles
Common sources of PM10 particles include sea salt, pollen and combustion activities such as motor vehicles and industrial processes. Dust from unsealed roads is a major source of PM10 particles.
How EPA monitors PM10
EPA measures PM10 at a number of stations using a monitor known as a TEOM. The data collected from these monitors is shown on the EPA AirWatch map.
PM10 air quality categories
The PM10 data on EPA’s website will be shown in different colours, depending on the level of PM10 in the air.
|Air quality category
||24-hr PM10 µg/m3
||One-hour PM10 µg/m3
||75 or greater
||120 or greater
Current standards for PM10
Air quality data collected by EPA is measured against national air quality standards, commonly known as the Ambient Air Quality NEPM. These standards are incorporated into the State Environment Protection Policy (Ambient Air Quality), with the exception of the PM10 annual standard.
Victoria has adopted a more stringent PM10 annual standard of 20 µg/m3. The reporting standards for PM10 particles are:
|25µg/m3 (Victorian standard 20µg/m3)
For one-hour PM10 data, EPA uses the value 80 µg/m3 as the level that triggers a ‘poor’ air quality category. There is currently no national standard for the one-hour PM10 average.