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Index of air quality in the world's major cities: September 20

Relaxnews
Tuesday 20 September 2011 11:46 BST
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(AFP PHOTO / NASA EARTH OBSERVATORY)

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Daily air quality index of some of the world's major cities on September 20, using data from AirNow, CITEAIR, and the American Embassy in Beijing.

City

  Average 19/09/2011                                                                   Average 20/09/2011                                                           

London

Madrid NA

Paris 

Brussels 

Berlin 

Prague 

Zurich 

Beijing NA NA
Beijing US embassy stats
Shanghai NA NA

Hong Kong

Brunei 
Seoul NA

New York 

San Francisco

Mexico City 

Montreal

NA

Toronto

NA
New Delhi 
Sydney 


The Air Quality Index (AQI) or Air Pollution Index (API) measures the parts of pollutant in a specified volume of air. The lower the AQI the fewer particles of pollution are in the air. For a more detailed explanation see http://www.airnow.gov/index.cfm?action=aqibasics.aqi.

All results are color-coded following the American AQI standard shown below. For all countries outside of Europe, the US and Canada, that region's definition of AQI terms has been accepted.

Legend 

Air Quality

 

Good

 

Moderate

 

Unhealthy for sensitive groups

 

Unhealthy

 

Very Unhealthy

 

Hazardous

Data: Data relating to Europe, the US and Canada is taken from CITEAIR - Common Information to European Air ( http://www.airnow.gov / http://www.airqualitynow.eu); data concerning China is taken from both official Chinese government sources and the US Embassy's automated air index Twitter account. For all countries the data displayed falls within either that country's definition of the level of air quality or the international AQI index. Data for all European, US and Canadian cities refers to background, not roadside, levels of air quality.

All data was collected at 8:15 am GMT on September 20.  http://www.airqualitynow.eu
http://www.airnow.gov

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