Monitoring the environment

EPA AirWatch air quality categories


EPA displays air quality information on EPA AirWatch using air quality categories. There are five categories in total, ranging from ‘Very good’ to ‘Very poor’. Each category is shown in a different colour.

When a pollutant reaches high levels, it will show as ‘Poor’ or ‘Very poor’. This means that the pollutant has exceeded its corresponding air quality standard.

Pollutant


Units
PM2.5
(24 hr)

µg/m3
PM2.5
(1 hr)

µg/m3
PM10
(1 hr)

µg/m3
CO
(8 hr)

ppm
SO2
(1 hr)

pbb
NO2
(1 hr)

pbb
O3
(1 hr)

pbb
Visibility
(1 hr)
Very good 0 – 8.2 0 – 13.1 0 – 26.3 0 – 2.9 0 – 65 0 – 39 0 – 33 0 – 0.77
Good 8.3 – 16.4 13.2 – 26.3 26.4 – 52.7 3.0 – 5.8 66 – 131 40 – 78 34 – 66 0.78 – 1.56
Fair 16.5 – 24.9 26.4 – 39.9 52.8 – 79.9 5.9 – 8.9 132 – 199 79 – 119 67 – 99 1.57 – 2.34
Poor 25.0 – 37.4 40 – 59.9 80 – 119.9 9.0 – 13.4 200 – 299 120 – 179 100 – 149 2.35 – 3.52
Very poor 37.5 or greater 60 or greater 120 or greater 13.5 or greater 300 or greater 180 or greater 150 or greater 3.53 or greater

Page last updated on 11 May 2017