What is an air quality index?

The Air Quality Index (AQI) is a standardized system used to communicate the quality of air in a specific area, reflecting the level of pollution and its potential health effects. It typically ranges from 0 to 500, with lower values indicating better air quality and higher values signifying worse conditions. The AQI is calculated based on the concentrations of various pollutants, such as particulate matter (PM), ozone (O3), carbon monoxide (CO), sulfur dioxide (SO2), and nitrogen dioxide (NO2). It helps inform the public about air quality and provides guidance on when to limit outdoor activities for health reasons.