Air Quality Index
The Air Quality Index, or AQI, much like an air quality “thermometer”, translates daily air pollution concentrations into a number on a scale between 0 and 500. The numbers in this scale are divided into six color-coded ranges, with numbers 0-300 as seen below.
(0-50) Good
No health impacts are expected when air quality is in this range.
(51-100) Moderate
Unusually sensitive people should consider limiting prolonged outdoor exertion.
(101-150) Unhealthy for Sensitive Groups
Active children and adults, and people with respiratory disease, such as asthma, should limit outdoor exertion.
(151-200) Unhealthy
Active children and adults, and people with respiratory disease, such as asthma, should avoid prolonged outdoor exertion; everyone else, especially children, should limit prolonged outdoor exertion.
(201-300) Very Unhealthy
Active children and adults, and people with respiratory disease, such as asthma, should avoid all outdoor exertion; everyone else, especially children, should limit outdoor exertion.