Air quality index

 
Alberta Environment produces this air quality rating to provide a qualitative measure of outdoor air, rated as Good, Fair, Poor or Very Poor.
 
The index converts hourly readings of five major air pollutants to a single value. A rating of 0-25 is Good, 26-50 is Fair, 51-100 is Poor and greater than 100 is Very Poor.
 
The five major air pollutants measured are: carbon monoxide, nitrogen dioxide, ozone, fine particulate matter (PM2.5) and sulphur dioxide.
 
The pollutant with the highest rating sets the air quality index for its monitoring station, for that specific hour.
 
Hypothetical example:
 
 Carbon monoxide  10  Good
 Fine particulate matter  12  Good
 Nitrogen dioxide  19  Good
 Ozone   30  Fair
 Sulphur dioxide  11  Good
 
Overall air quality index rating for this station at this time would be Fair, based on its ozone index.
 
The air quality index is reported hourly from 23 air monitoring stations in the province. The Current Air Quality Website also displays in real-time other parameters collected at an additional 20 air monitoring stations in Alberta.

Current air quality is also available by calling (780) 427-7273 in the Edmonton area and toll-free 1-877-247-7333 for the rest of Alberta.

See CASA Data Warehouse for more on the Air Quality Index calculations.