Air quality is a vital determiner of quality of life around the world, as the worse it is, the more health problems people may experience. Various factors can impact this quality, from run-of-the-mill pollution to environmental catastrophe. The latter is often the most dangerous, and one is happening right now in the US.What is the air quality index?
The air quality index measures pollutants and the dangers they pose.
The index attaches a value to the measured quality, which ranges from zero to 500.
The highest band indicates high levels of one or several types of pollutant.
Air quality indexes measure the five following pollutants:Ground-level ozoneParticle pollution (also known as particulate matter, including PM2.5 and PM10)Carbon monoxideSulfur dioxideNitrogen dioxideWhat does hazardous air quality mean?
Most countries use the same index, but divide it differently and take varying actions to bring it back to an acceptable level.
In the US, air quality is divided into six categories, ranging from green to maroon.
The lowest, green is "good", followed by moderate, unhealthy for sensitive groups, unhealthy, very unhealthy, and hazardous.
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Officials attach the following warnings to their AQI analysis:Good (0 to 50): Air quality is satisfactory, and air pollution poses little or no risk.Moderate (51 to 100): Air quality is acceptable. However, there may be a risk for some people, particularly those who are unusually sensitive to air pollution.Unhealthy for Sensitive Groups (101 to 150): Members of sensitive groups may experience health effects. The general public is less likely to be affected.Unhealthy (151 to 200): Some members of the general public may experience health effects; members of sensitive groups may experience more serious health effects.Very Unhealthy (201 to 300): Health alert: The risk of health effects is increased for everyone.Hazardous (301 and higher): Health warning of emergency conditions: everyone is more likely to be affected.
Most people with health problems should keep an eye on the air quality, especially if they live in an area prone to wildfires.
According to Columbia University, they will need to take precautions if it gets too high.
The university advises: "During air quality alerts, the vulnerable should reduce physical exertion and try to stay indoors with the windows closed.
"Those with asthma should carry their inhalers and use a face mask if they go outdoors."