Question

What does AQI mean?

Answer 1

AQI stands for Air Quality Index; it is the rank which defines the quality of air. The daily air quality conditions are reported to provide information to the public about the quality of air they breathe and to understand its harmful effects on human health.

Complete step by step answer:
AQI of India is calculated depending on 8 major pollutants they are ${{S}}{{{O}}_{{2}}}{{, N}}{{{O}}_{{2}}}{{, PM2}}{{.5, PM10, CO, }}{{{0}}_{{3}}}{{, N}}{{{H}}_{{3}}}{{, Pb}}$. The contribution of these pollutants helps to determine the AQI. PM stands for particulate matter i.e., in ${{PM2}}{{.5}}$ the particulate size is ${{2}}{{.5 \mu m}}$ and in ${{PM10}}$ the particulate matter is ${{10 \mu m}}$. If the value of AQI is below 50 than the air quality is good, if the AQI is between the range of 50 to 100 then air quality is acceptable for API between 101 to 150 highly sensitive people could be affected and if the API range is between 151 to 200 then the general public may get some health effects, API range from 201 to 300 is health alert as there is a risk of health effects and the API from 301 and higher is an emergency health warning conditions.

Additional information:
Higher the AQI score worse is its effect. AQI is looking at the composite materials of different pollutants. Among these pollutants ${{PM2}}{{.5}}$ is a serious one with a particulate matter of ${{2}}{{.5 \mu m}}$because these are the very tiny particles that enter into the lungs and bloodstream causing serious health issues with the lungs and heart. Long term exposure can lead to chronic respiratory diseases.

Note: ${{PM2}}{{.5}}$ comes from vehicle combustions, forest fires, power plant emissions particularly those involving coal burning.
${{PM10}}$ has a particulate matter less than ${{10 \mu m}}$ but greater than ${{2}}{{.5\mu m}}$ in size. These particles cause eye and throat irritation. AQI is reported in ${{\mu g/}}{{{m}}^{{3}}}$. PM2.5 particles do more damage than ${{PM10}}$ particles. Human hair is ${{50 \mu m}}$ in diameter and PM10 is $\dfrac{{{1}}}{{{5}}}$ the size and PM20 is $\dfrac{{{1}}}{{{{20}}}}$ the diameter of human hair
Certified N95 masks when worn properly confirmed to filter ${{95 \% }}$ of particles greater than ${{0}}{{.3 \mu m}}$ size. By wearing N95 masks the exposure to most ${{PM2}}{{.5}}$ particles are reduced by least ${{95 \% }}$.