The AQI or Air Quality Index will let you know on a daily basis how clean the air is. It measures the quantity of ozone, particle pollution (also known as particulate matter), carbon monoxide, sulfur dioxide, and nitrogen dioxide. Ground-level ozone and particulates are the most dangerous air pollutants to humans. The Index is based on a 500 point scale with "0" being the cleanest air and "500" being the most polutted air. The index is color coded for easy reference. Here are the colors and their meaning along with a link to the page:
1) Green Color (0-50) "Good Air Quality:" Air pollution poses little if any, health risk.
2) Yellow Color (51-100) "Moderate Air Quality:" indicates air that is safe for most people to breath. A few folks with severe respiratory problems may have difficulty breathing.
3)Orange (101-150) "Unhealthy for Sensitive Groups:" means people with lung heart problems may experience health effects. The general public is not likely to be affected.
4) Red Color (151-200)"Unhealthy:" Everyone may begin to experience health effects such as sneezing & wheezing. People with lung or heart problems may experience more serious health effects.
5) Purple Color (201-300) "Very Unhealthy:" At this level, health alerts are often issued. Everyone breathing the air may experience serious health effects.
6) Maroon Color (> 300) "Hazardous:" This is terrible air quality! Health warnings and emergency conditions would likely exist. The entire population is likely to be affected.