What is Air Quality Index and how is it calculated?

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.
India uses the National Air Quality Index (AQI), Canada uses the Air Quality Health Index, Singapore uses the Pollutant Standards Index and Malaysia uses the Air Pollution Index.
There are many cities including Beijing, Paris where 'pollution emergency' is declared. However, India also declared the same in November 2019.
What is Air Quality Index
The National Air Quality Index (AQI) in India was launched on 17 September 2014 in New Delhi under the Swachh Bharat Abhiyan by the Environment Minister Shri PrakashJavadekar. The air quality index is composed of 8 pollutants ((PM10, PM2.5, NO2, SO2, CO, O3, NH3, and Pb).
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.
As the air quality deteriorates, so does the ranking of air from good to bad then very poor to severe.
Air pollution means the amount of Sulfur Dioxide (SO2), Nitrogen Dioxide (NO2), and Carbon Monoxide (CO) in the air exceeds the criteria set by the World Health Organization (WHO).
In cities like Delhi, the main components of air pollution are the PM 2.5 and PM 10 particles that are present in the air. When the level of these particles rises in the air, they cause difficulty in breathing, irritation in the eyes, etc.
According to the Berkeley Earth science research group; breathing in air with a PM2.5 content of between 950 to 1,000 is like smoking 44 cigarettes a day.
What does the Air Quality Index Show?
AQI |
Associated Health Impacts |
Good (0–50) |
Minimal Impact |
Satisfactory (51–100) |
May cause minor breathing discomfort to sensitive people. |
Moderately polluted (101–200) |
May cause breathing discomfort to people with lung disease such as asthma, and discomfort to people with heart disease, children and older adults. |
Poor (201–300) |
May cause breathing discomfort to people on prolonged inhaling, and problems to people with heart disease. |
Very Poor (301–400) |
May cause respiratory illness to the people on prolonged inhaling. Effect may be more severe in people who are living with lung and heart diseases. |
Severe (401-500) |
May cause respiratory impact even on healthy people, and serious health impacts on people with lung/heart disease. The health impacts may be experienced even during normal walk also. |
Source:www.cpcb.nic.in
Causes of Air Pollution in Delhi
1. Reduced airflow
2. use of excessive firecrackers and other lightening on the occasion of Diwali.
3. Stubble burning by farmers of Haryana and Punjab
4. Extreme increase in the number of vehicles
Measures to Control Air Pollution
The Central Pollution Control Board (CPCB) along with the State Pollution Control Board (SPCB) is conducting the National Air Monitoring Program (NAMP) covering 240 cities in the country with more than 342 monitoring stations.
The government has taken several steps to control air pollution in New Delhi, these measures include promoting CNG based transport as per auto fuel policy, implementing Odd-Even formula, spraying water on trees, temporary ban on construction activities, road cleaning through vacuum cleaner, strengthening public transport, stopping operation of coal-based thermal power projects, etc.
In the end, it would be wise to say that it is not the right practice to blame the government for every problem, people's participation is very important to solve any problem.
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