The air quality is measured by the Air Quality Index. Air quality indices have been created in different countries for the measurement of air quality. These indices measure the air quality in the country and indicate whether the amount of nitrogen dioxide, carbon monoxide and sulfur dioxide in the air exceeds the criteria set by the World Health Organization or not.

The Air Quality Index measures the quality of air. It shows the amount and types of gases dissolved in the air. There are 6 categories of the air have been created in this air quality index. 

These categories are based on air quality. These categories are; good, satisfactory, moderate, poor, very poor and severe. 

 

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