Particulate matter
Particles are classified by their size with PM10 referring to inhalable particles smaller than 10 microns (μm) in diameter. Of the inhalable particles, those smaller than 2.5 microns (PM2.5) can penetrate more deeply into the respiratory system and therefore pose the greatest risk to health (see diagram of particle sizes).
Benchmarking & Resources has more information on the guidelines and standards used for the following summary tabs.
PM10
Annual summary
The map shows annual average PM10 (μg/m3) measured at core monitoring sites across the region. Results are shown as a percentage of the national guideline which is an annual average of 20 μg/m3. The regional target is 13 μg/m3 or lower which is based on air quality being maintained at the ‘acceptable’ or better category which corresponds to no more than 66% of the national guideline (green to dark blue).
The table also shows the annual summary for PM10 reported as a 24-hour average from core monitoring sites across the region. The national standard allows one high pollution day per year which is a 24-hour average above 50 μg/m3 (or the 2nd highest 24-hour average to be below 50 μg/m3).The regional target is a maximum 24-hour average of 33 μg/m3.
- Drag and scroll on the map to move and zoom in on areas of interest.
- Hover on the site circles to see more information.
- Use the selection box ( ) to subset the map and table data to that area.
- Click on sites in the table to highlight them on the map.
- Use the arrows ( ↓↑ ) next to the table headers to sort the data.
All values in μg/m3. Data capture (%) refers to the proportion of total days per year with at least 18 hours data present.
24-hour averages
The graphs show 24-hour average PM10 levels from core monitoring sites. The colour bands show percentages of the national standard which is a 24-hour average of 50 μg/m3. High pollution days are those days above 100% of the standard. The regional target is 33 μg/m3 or lower which is based on air quality being maintained at the ‘acceptable’ or better category which corresponds to no more than 66% of the national standard (from green to dark blue). Hover over the graphed days to see specific values.
Trends annual average
The graphs show trends in annual average PM10 levels from core monitoring sites. The colour bands show percentages of the national guideline which is 20 μg/m3 - from green (less than 10% of the standard) to red (more than 100% of the standard). The regional target is an annual average of 7 μg/m3 or lower which is based on air quality being maintained at the ‘acceptable’ or better category which corresponds to no more than 66% of the national guideline (green to dark blue). Hover over the graphed years for specific values.
Note: only previous years with at least 75% data capture (ie, 274 days with data present) are shown. Results for years marked with * have been adjusted to account for a change in monitoring instrument.
Trends high pollution days
This table shows the number of high pollution days per year, which are PM10 24-hour averages above the national standard limit of 50 μg/m3. The standard allows one day per year to be above this limit.
PM2.5
Annual summary
The map shows annual average PM2.5 (μg/m3) from core monitoring sites across the region. Results are shown as a percentage of the World Health Organization guideline (WHO) which is 10 μg/m3. The regional target is 7 μg/m3 or lower which is based on air quality being maintained at the ‘acceptable’ or better category which corresponds to no more than 66% of the guideline (green to dark blue).
The table also shows the annual summary for PM2.5 reported as 24-hour averages from core monitoring sites across the region. High pollution days are those days above 100% of the guideline. The WHO guideline allows three high pollution days per year which is a 24-hour average above 25 μg/m3 (or the 4th highest 24-hour average to be below 25 μg/m3). The regional target is a maximum daily average of 17 μg/m3 which corresponds to no more than 66% of the guideline.
- Drag and scroll on the map to move and zoom in on areas of interest.
- Hover on the site circles to see more information.
- Use the selection box ( ) to subset the map and table data to that area.
- Click on sites in the table to highlight them on the map.
- Use the arrows ( ↓↑ ) next to the table headers to sort the data.
All values in μg/m3. Data capture (%) refers to the proportion of total days per year with at least 18 hours data present.
24-hour averages
The graphs show 24-hour average PM2.5 levels from core monitoring sites. The colour bands show PM2.5 levels relative to a percentage of the World Health Organization guideline which is 25 μg/m3 - from green (less than 10% of the standard) to red (more than 100% of the standard). The regional target is 17 μg/m3 or lower which is based on air quality being maintained at the ‘acceptable’ or better category which corresponds to no more than 66% of the guideline (from green to blue). Hover over the graphed days to see specific values.
Trends annual average
The graphs show trends in annual average PM2.5 levels from core monitoring sites. The colour bands show PM2.5 levels relative to a percentage of the World Health Organization guideline which is 10 μg/m3 - from green (less than 10% of the standard) to red (more than 100% of the standard). The regional target is 7 μg/m3 or lower which is based on air quality being maintained at the ‘acceptable’ or better category which corresponds to no more than 66% of the guideline (from green to blue). Hover over the graphed years for specific values.
Note: only previous years with at least 75% data capture (ie, 274 days with data present) are shown. Results for years marked with * have been adjusted to account for a change in monitoring instrument.
Trends high pollution days
This table shows the number of high pollution days per year, PM2.5 24-hour averages above the World Health Organization guideline limit of 25 μg/m3. The guideline allows three days per year to be above this limit.
