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Saint Charles, MO 63301

Air Quality

Today's Air Quality - Saint Louis, MO
Date	Code	AQI Level	Major Pollutant
5/25/2013 6:00 PM		36	Small Particulate Matter
Air Quality Forecast - Saint Louis, MO
Date	Code	AQI Level	Major Pollutant
5/25/2013		N/A	Ozone
5/25/2013		N/A	Ozone
5/26/2013		N/A	Ozone

Air Quality Index (AQI) Scale
AQI Color	AQI Category	AQI Numbers
	Good	0-50
	Moderate	51-100
	Unhealthy for Sensitive Groups	101-150
	Unhealthy	151-200
	Very Unhealthy	201-300
	Hazardous	301-500+

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What is AQI?

The AQI is an index for reporting daily air quality. It tells you how clean or polluted your 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. EPA uses the AQI for five major air pollutants regulated by the Clean Air Act: ground-level ozone, particulate matter, carbon monoxide, sulfur dioxide, and nitrogen dioxide. For each of these pollutants, EPA has established national air quality standards to protect against harmful health. (EPA-454K-03-002, August 2003, http://www.airnow.gov/)