North American Air Pollution Statistics

About the Air Quality Levels

AQI	Air Pollution Level	Health Implications	Cautionary Statement (for PM2.5)
0 - 50	Good	Air quality is considered satisfactory, and air pollution poses little or no risk	None
51 -100	Moderate	Air quality is acceptable; however, for some pollutants there may be a moderate health concern for a very small number of people who are unusually sensitive to air pollution.	Active children and adults, and people with respiratory disease, such as asthma, should limit prolonged outdoor exertion.
101-150	Unhealthy for Sensitive Groups	Members of sensitive groups may experience health effects. The general public is not likely to be affected.	Active children and adults, and people with respiratory disease, such as asthma, should limit prolonged outdoor exertion.
151-200	Unhealthy	Everyone may begin to experience health effects; members of sensitive groups may experience more serious health effects	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	Health warnings of emergency conditions. The entire population is more likely to be affected.	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.
300+	Hazardous	Health alert: everyone may experience more serious health effects	Everyone should avoid all outdoor exertion

To know more about Air Quality and Pollution, check the wikipedia Air Quality topic or the airnow guide to Air Quality and Your Health.

For very useful health advices of Beijing Doctor Richard Saint Cyr MD, check www.myhealthbeijing.com blog.

Worst
	Park Place, Houston, Texas, Texas on 2017-07-25 10:00:00 graph 0	103
	Houston Deer Park #2, Houston, Texas, Texas on 2017-07-25 10:00:00 graph 1	102
	CPS Pecan Valley, San Antonio, Texas, Texas on 2017-07-25 10:00:00 graph 2	100
	Heritage Middle School, San Antonio, Texas, Texas on 2017-07-25 10:00:00 graph 3	100
	Westlake site, Louisiana, USA on 2017-07-25 12:00:00 graph 4	95
	National Seashore, Corpus Christi, Texas, Texas on 2017-07-25 10:00:00 graph 5	93
	Houston East, Houston, Texas, Texas on 2017-07-25 10:00:00 graph 6	92
	Clinton, Houston, Texas, Texas on 2017-07-25 10:00:00 graph 7	92
	Seabrook Friendship Park, Houston, Texas, Texas on 2017-07-25 10:00:00 graph 8	89
	Selma, San Antonio, Texas, Texas on 2017-07-25 10:00:00 graph 9	89

Best
	Intermediate School 74, New York, USA on 2017-07-25 09:00:00 graph 0	1
	Cold Lake South, Alberta, Canada on 2017-07-25 10:00:00 graph 1	1
	Calgary Northwest, Alberta, Canada on 2017-07-25 10:00:00 graph 2	2
	Intermediate School 143, New York, USA on 2017-07-25 09:00:00 graph 3	2
	North Braddock, Allegheny, Pennsylvania, USA on 2017-07-25 10:00:00 graph 4	2
	Grand Forks City Hall, British Comlumbia on 2017-07-25 07:00:00 graph 5	3
	Genesee, Alberta, Canada on 2017-07-25 08:00:00 graph 6	3
	Maspeth, New York, USA on 2017-07-25 09:00:00 graph 7	4
	Fresh Kills West, New York, USA on 2017-07-25 09:00:00 graph 8	4
	Beach Road VDOT, Richmond, USA on 2017-07-25 10:00:00 graph 9	5

Top 10 Best and Worst Air Quality in North America