The Air Quality Index (AQI) is a standardized system for measuring and communicating air pollution levels. It provides a simple scale, ranging from 0 to 500, where higher values indicate worse air quality and greater health risks. The AQI is designed to help the public understand air pollution levels and take necessary precautions. Unlike a single-pollutant measurement, the AQI considers the concentration of multiple key air pollutants, including:
- Particulate Matter (PM): Tiny airborne particles, including PM2.5 (smaller than 2.5 micrometers) and PM10 (smaller than 10 micrometers). These particles can penetrate deep into the lungs, causing respiratory and cardiovascular issues.
- Ground-level Ozone (O₃): A harmful gas formed by the reaction of pollutants with sunlight. It can irritate the respiratory system, trigger asthma attacks, and reduce lung function.
- Nitrogen Dioxide (NO₂): Emitted from vehicle exhaust and industrial activities, it can cause inflammation of the airways and increase susceptibility to respiratory infections.
- Sulfur Dioxide (SO₂): Released mainly from burning fossil fuels, it can irritate the respiratory tract and lead to lung diseases.
- Carbon Monoxide (CO): A colorless, odorless gas produced by incomplete combustion of fuel. At high concentrations, it can reduce oxygen delivery to the body, leading to serious health effects.