Most air pollution caused by human activities is the result, whether directly or indirectly, of burning fuels in a furnace or engine. Examples of fuels burned that produce air pollution are coal, natural gas, oil and gasoline. These fuels are burned to produce electricity and power vehicles.
One of the biggest consequences of air pollution is its impact on human health. Air pollution contributes to respiratory diseases such as chronic bronchitis, asthma, lung cancer and emphysema. Air pollution can also harm and destroy plant and animal life, and it damages property.
There are two types of widespread air pollution. The first type of pollution is known as smog, and the second type is known as soot. Significant pollutants that make up smog and soot include sulfur, nitrogen and carbon monoxide. Smog occurs when pollutants become trapped close to the ground.
The burning of fossil fuels contributes to the largest amount of air pollution mostly due to the fact that many human activities are directly related to the use of gasoline and other fuels in order to keep items such as engines and furnaces running. The largest source of air pollution due to fossil fuels being burned is vehicles. Due to their large number and the length of time they are run, carbon monoxide, the gas given off by trucks and cars, is constantly released into the air.
Another form of air pollutant produced by vehicles is carbon dioxide, which is not considered as deadly as carbon monoxide, which causes adverse health effects. It is closely related to the greenhouse effect, which is considered to be the cause of the warming of the earth.
Outside of burning fossil fuels, other pollutants are released into the air due to the burning of certain materials. Particulate matter is the direct result of burning items such as wood and plants, which happens both from human activity and natural fires.
Several devices and systems have been created to either reduce or prevent industrial air pollution. For example, electrostatic precipitators remove pollutant particles by charging them electrically and collecting them on electrodes with an opposite charge. Cyclone separators rotate impure air with enough force to hurl particles against the side walls of the separator. Scrubbers remove impurities in the air through water sprays.