Air Pollution Essay Research Paper Air PollutionIntroductionAir — страница 2

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particulates are brutal primary pollutant. Their presence in the atmosphere has diminished sharply during the past 29 years. Since 1975, the concentration of lead has decreased by more than 90%, which can be directly linked to the elimination of lead from gasoline. The following table shows that huge drop. TABLE 2 Gas Another primary group of pollutants consists of the surfur oxides(Sox), and the major contributor is SO2, a sulfur dioxide. This is generated whenever sulfur is burned, most often where fuel with a high sulfur content is used. Coal can have very high sulfur concentrations, as can some oil. Overall, coal and oil are the major sources for sulfur oxide pollution. The vast majority of this type of air pollution comes from generation of heat and electricity. These

stationary sources account about 80% of all sulfur oxides. Transportation’s contribution is minor, about 5%. The rest comes from industry. Sulfur dioxides cause damage to vegetation and material. Plants lose their chlorophyll which is the plants food factory. But the most damage appears when sulfur oxides combine with other substances. Because of its solubility, sulfur dioxide becomes a major contributor to acid deposition. Leaves are bleached and show damage. Tree growth is stunted and vegetation dies. Damage to vegetation occurs at concentrations lower than what is harmful to people. Carbon monoxide (CO) Carbon monoxide is colorless, odorless , tasteless,non-corrosive, highly poisonous gas of about the same density as that of air. It is very flammable, burns in air with

bright blue flame. Its melting point is at-205.0. C and boiling point is at -191.5. C. There is no way to know if it is around, except we may no feel so well. When a fire burns in an enclosed space, oxygen is gradually depleted and carbon dioxide is increased. The changes in both of the these gases increasingly cause the combustion process to change from one of complete combustion to one of incomplete combustion, resulting in the release of increasing amounts of CO. Thus, even a perfectly designed and adjusted furnace or water heater (or any kind of combustion device) will eventually begin producing toxic/lethal amounts of CO if it operates in a closed space and/or where insufficient fresh air is available. Table three lists some of the effects of CO to humans. TABLE 3 CO

concentration in Parts Per Million or as as percentage of air % of CO in air Inhalation time and toxic symptoms developed 0.0001% Normal background levels 0.0009% Maximum allowable concentration short term in living area 0.0025% Maximum exposure TWA (Time Weighted Average) in the workplace. 0.005% Maximum exposure allowed (OSHA) in the workplace. 0.02% Mild headache, fatigue, nausea and dizziness. 0.04% Serious headache – other symptoms intensify. Life threatening after 3 hours. 0.08% Dizziness, nausea and convulsions Dead within 2 to 3 hours 0.16% Headache, dizziness and nausea. Death within 1 – 2 hours. 0.32% Headache, dizziness and nausea. Death within 1 hour. 0.64% Headache, dizziness and nausea. Death within 25 – 30 minutes. 1.28% Death within 1 – 3 minutes. Control

of Air Pollution The Regulations The early air pollution laws were passed within small communities and concerned the color and density of the smoke that comes out from the stacks. They first appeared in Chicago and Cincinnati and later on began to show up also in other communities. A special chart determined the level of smoke. The chart showed smoke with different shades of gray and black. At a particular level violations would be set. No national air pollution legislation appeared until the 50’s. The first federal legislation appeared in 1955 when the Air Pollution Control Act was passed. In 1965 the Motor Vehicle Air Pollution Act was passed, establishing national automobile emission regulations for the first time. Then the Air Quality Act of 1967 was passed, providing funds

for additional federal research and designating air quality control regions to help establish air pollution criteria. Another goal of this act was to research the cost -effectiveness relation of available engineering control techniques. Later, during the 70’s National Air Quality Standards were set for the major pollutants. Primary standards were set for health, with secondary standards for vegetation and general environmental welfare. Penalties as high as $25.000 per day and a year in prison were authorized for industries that failed to meet the regulations. Automobiles emission standards were set. Additional adjustments to the 70’s regulation came along in 1990. Each revised some of the older regulations. Some of which proved to be very strict and unattainable. Overall each