aqi

The aqi crate provides functions for calculating the Air Quality Index based on concentrations of particuate matter.

The AQI is defined for ozone (O₃), 1.0-2.5 micron particulate matter (PM2.5), 2.5-10 micron particulate matter (PM10), carbon monoxide (CO), sulfur dioxide (SO₂), and nitrogen dioxide (NO₂).

The AQI helps make air quality more understandable to laypersons, normalizing air quality on a scale from 0 to 500, with round-number ranges that indicate qualities such as "Good", "Unhealthy", and "Hazardous".

For further information, see AQI basics and AQI techinical assistance.

Additionally, this library supports "adjusted" PM2.5 AQI values, using the LRAPA and AQandU conversion formulas.