The Air Quality Index (AQI) is used to assess air quality of a place. The AQI is a thermometer that ranges from 0- 500 degrees F. The AQI instead of indicating changes in temperature, shows changes in the amount of pollution in the air. When the AQI is less than 50, the air quality is considered good. The risk to human health grows as the AQI number increases. You can refer to image for further reference.

As we know that majority of the air in our atmosphere consists of two gases that are required for life on Earth: N2 and O2. Many other gases and particles, on the other hand, are present in lower levels in the air. The AQI monitors five key contaminants in the air:  Ground level ozone, CO, SO2, NO2 and Airborne particles. The two air pollutants cause great harm to human health are ground level ozone and airborne particles. Ozone is a gas that forms a layer high in the Earth's atmosphere and this ozone layer is beneficial because it shields us from the Sun's damaging radiation. Ground-level ozone is harmful to human health. When sunlight interacts with specific chemical emissions, it produces this substance (for example nitrogen dioxide, carbon monoxide and methane).

Geostationary Operational Environmental Satellites-R Series satellites monitors particle pollution in our atmosphere. Also, The Joint Polar Satellite System (JPSS) also gathers data on particles in the atmosphere.

Another interesting topic is, Is it possible to test the air quality in my home?

Although outdoor air pollution is a major concern, keeping adequate indoor air quality is as important for our good health. According to studies, we spend 80 to 90% of our days indoors on average, and the air we breathe is frequently polluted. New furniture, cleaning and cosmetic goods, and paints are all causes of pollution. Individuals who have access to this level of personal pollution data have been shown to be better able to protect themselves and their loved ones, reducing their overall exposure to air pollution. Personal pollution sensors are smaller and more accessible than their government-issued equivalents, and they allow people to not only assess the quality of indoor air but also track their exposure over time. Plume Labs' Flow personal air quality monitor analyzes particle matter (PM10, PM2.5, and PM1), NO2, and Volatile organic compounds (VOCs).

 

Reference: https://scijinks.gov/air-quality/