Vehicle Pollutants
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| What Are Car Emissions? | |||||||||||||||||||||
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| According to the U.S. Environmental Protection Agency (EPA), driving a car is the single most polluting thing that most of us do. Motor vehicles emit millions of tons of pollutants into the air each year. In many urban areas, motor vehicles are the single largest contributor to ground-level ozone, a major component of smog. Ground-level ozone is the most serious air pollution problem in the northeast and mid-Atlantic states. Cars also emit several pollutants classified as toxins, which cause as many as 1,500 cases of cancer in the country each year. Auto emissions also contribute to the environmental problems of acid rain and global warning. | |||||||||||||||||||||
| Vehicle Improvements | |||||||||||||||||||||
| Pollution control measures have drastically reduced emissions per vehicle in the past 20 years. However, during that time the total miles traveled has doubled, resulting in higher levels of air pollutants in many parts of the country. | |||||||||||||||||||||
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Vehicle Pollutants
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| Motor vehicles generate pollutants because the combustion process is not perfect. If we could achieve complete combustion in the engine the hydrogen atoms in gasoline would combine with oxygen atoms from the air and form water (H2O). The carbon atoms in gasoline would combine with oxygen atoms from the air to form Carbon Dioxide (CO2). If complete combustion could be achieved there would be no harmful pollutants emitted from the tail pipe. New engine designs and electronic controls have moved closer to achieving perfect combustion but, the American public is driving more miles every year, so we are still stuck trying to clean up our air. Incomplete combustion produces the following pollutants that we must try to keep to a minimum. | |||||||||||||||||||||
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| Hydrocarbons (HC) are particles of raw unburned fuel. When HC is released it reacts with nitrogen oxides in the presence of sunlight and elevated temperatures to form ground-level ozone. It can cause eye irritation, coughing, wheezing, and shortness of breath and can lead to permanent lung damage. | |||||||||||||||||||||
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| Carbon Monoxide (CO) is formed when incomplete combustion occurs. CO is a colorless, odorless, deadly gas. It reduces the flow of oxygen in the bloodstream and can impair mental functions and visual perception. In urban areas, motor vehicles are responsible for as much as 90 percent of carbon monoxide in the air | Oxides of Nitrogen (NOx) is created when multiple oxygen atoms combine with a nitrogen atom. NOx is formed in the combustion chamber when the internal cylinder temperatures climb above 2,500ºF. NOx contributes to the formation of ozone and contributes to the formation of acid rain causing water quality problems | ||||||||||||||||||||
| Oxides of Sulphur (SOx) are formed in vehicles with catalytic converters. The oxidizing process in the converter allows the sulphur (found in all gasoline) to combine with oxygen creating SOx. This pollutant attacks and deteriorates textiles, building materials and vegetation. | Carbon Dioxide (CO2) is formed during the combustion process when carbon atoms combine with oxygen atoms. CO2 has a potential to trap the Earths heat and cause global warning. | ||||||||||||||||||||
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