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Sulfur Dioxide (SO2)


Sulfur oxides (SOx) are colorless gases that are the result of burning sulfur. All fuels used by man (oil, coal, natural gas, wood, etc.) contain some sulfur, and during the combustion process, sulfur reacts with oxygen to form SOx. The primary source of sulfur oxides is the burning of these fossil fuels, particularly coal, at industrial facilities. Sulfur dioxide(SO2) is used as an indicator of all SOx concentrations in the ambient air, because it is the most easily measured.

Sulfur dioxide is known to irritate the respiratory system. SO2 is particularly detrimental to individuals who suffer from respiratory diseases such as asthma and chronic bronchitis. SO2 can also combine with particles and moisture in the air creating an even greater health risk. It contributes to the formation of acid rain by transforming into sulfuric acid in the atmosphere. Acid rain can damage lakes and aquatic life, building materials, and plant life.

Sulfur dioxide emissions from combustion at power plants are controlled by "scrubbing" the gas leaving the plant or by removing sulfur from the fuel before it is burned. Individuals can reduce SO2 emissions by limiting the use of electricity, by turning off electric devices not in use, and by making use of more efficient electric devices (lights, refrigerators, motors, etc.) and alternate energy sources.