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Air Quality Index

The Air Quality Index (AQI) is a tool for reporting daily air quality. It tells you how clean or polluted the air is, and what associated health concerns you should be aware of. The AQI focuses on health effects that can happen within a few hours or days after breathing polluted air. The AQI is reported for five major air pollutants regulated by the Clean Air Act: ground-level ozone, particulate matter, carbon monoxide, sulfur dioxide, and nitrogen dioxide. Useful health information about daily air quality, including near real-time AQI values for continuous ozone and particulate matter monitors, is available via the MIair web page. For a cautionary guide for each range of exposure, view the Health Advisory Chart. To view the corresponding chart of actions that may be needed to protect health as pollution levels increase, please click here.

The Environmental Protection Agency has revised the AQI breakpoints to reflect recent changes to the National Ambient Air Quality Standards for ground-level ozone and fine particulate matter (PM2.5). Currently, daily ozone concentrations above 0.075 ppm, or fine particulate matter concentrations above 35.4 µg/m3, activate the "unhealthy for sensitive groups" category - known to some people as a "code orange" air quality day. When levels reach this category, certain groups should adjust their physical activity to reduce their exposure. These sensitive groups include children and adults who are active outdoors, people with asthma or other lung diseases, and older adults.

Air Quality Index Logo

 

 

 

 

 

Air Quality Index
Values
Air Quality
Descriptor
Ozone Concentration (ppm)
(8-hour average, unless noted)
Particulate Matter Concentration
(µg/m3)
(24-hour average)
0 to 50 Good 0.0 to 0.059 0.0 to 12.0
51 to 100 Moderate 0.060 to 0.075 12.1 to 35.4
101 to 150 Unhealthy for Sensitive Groups 0.076 to 0.095 35.5 to 55.4
151 to 200 Unhealthy 0.096 to 0.115 55.5 to 150.4
201 to 300
Very Unhealthy
0.116 to 0.374
150.5 to 250.4

 

Health Chart

Air Quality Level
Air Quality Index
Health Advisory for Particle Pollution and Ozone
Good
0-50
None

Moderate
51-100
Unusually sensitive people should consider limiting prolonged outdoor exertion.

Unhealthy for Sensitive
Groups
101-150
People with heart disease or lung disease, such as asthma; children and older adults; and people who are active outdoors should reduce prolonged outdoor exertion.
Unhealthy
151-200
People with heart disease or lung disease, such as asthma; children and older adults; and people who are active outdoors should avoid prolonged or heavy outdoor exertion. Everyone else should reduce prolonged outdoor exertion.

Very Unhealthy
201-300
People with heart disease or lung disease, such as asthma; children and older adults; and people who are active outdoors should avoid all outdoor physical activity and exertion. Everyone else should avoid prolonged or heavy exertion.

 

The West Michigan Clean Air Coalition is a partnership of businesses, academic institutions, government agencies, industry, and non-profit organizations in Kent, Ottawa, Muskegon, and Kalamazoo counties working together to achieve cleaner air in the region through the education and promotion of voluntary emission reduction activities.

©2006 West Michigan Clean Air Coalition. All Rights Reserved. | E-Mail the Webmaster | Page last updated Wednesday, June 19, 2013.