Air pollution - Wikipedia, the free encyclopedia. For the obsolete medical theory, see Bad air. For the measure of how polluted the air is, see Air quality index. For the properties of air, see Qualities of air. Modern-Aire Designer Program. Valiant Sales offers a design trade only program for custom range hoods beautifully made by. The Federal Energy Management Program's Energy Incentive Program helps federal agencies take advantage of these. FEMP provides information about the availability of energy-efficiency and renewable-energy project. American Institutes for Research. About Us; Our Topics; Client Services; News & Events; global-literacy-day-spotlight.jpg. International Literacy Literacy empowers individuals, communities, and societies. Supporting efforts to. AIRE; RPAS; SESAR Concepts; SESAR and global interoperability. Global cooperation in standardisation. Eurocontrol renews commitment to SESAR project. SESAR delivers the recommendations of the VDL Mode 2. Stay in touch Keep up with all things Google Earth via Google+ and Twitter, and our Lat Long blog and Sightseer newsletter. Clean Vehicle Rebate Project. This page last updated April 8, 2016. The Air Resources Board (ARB) Clean Vehicle Rebate Project (CVRP) is designed to promote the purchase of battery electric, plug-in hybrid electric. The landing site for Project Bader, the RAF Air Cadets internal management system. This portal provides access to resources for all Air Cadet Staff. Air pollution is the introduction of particulates, biological molecules, or other harmful materials into Earth's atmosphere, causing diseases, allergies, death to humans, damage to other living organisms such as animals and food crops, or the natural or built environment. Air pollution may come from anthropogenic or natural sources. The atmosphere is a complex natural gaseous system that is essential to support life on planet Earth. Indoor air pollution and urban air quality are listed as two of the world's worst toxic pollution problems in the 2. Blacksmith Institute World's Worst Polluted Places report. The substance can be solid particles, liquid droplets, or gases. Airport Cooperative Research Program; Airport Improvement Program (AIP) Airport Safety; Engineering. Details of NextGen benefit calculations can be found in the 'Update to the Business Case for the NextGen based on the. Welcome to Prezi, the presentation software that uses motion, zoom, and spatial relationships to bring your ideas to life and make you a great presenter. A pollutant can be of natural origin or man- made. Pollutants are classified as primary or secondary. Primary pollutants are usually produced from a process, such as ash from a volcanic eruption. Other examples include carbon monoxide gas from motor vehicle exhaust, or the sulfur dioxide released from factories. Secondary pollutants are not emitted directly. Rather, they form in the air when primary pollutants react or interact. Ground level ozone is a prominent example of a secondary pollutant. Some pollutants may be both primary and secondary: they are both emitted directly and formed from other primary pollutants. SO2 is produced by volcanoes and in various industrial processes. Program Information; EXISTING RESERVATIONS; Sign in to your HHonors account to discover special rates. Go Hilton is available to all employees at Hilton Worldwide corporate offices and its owned and managed. Coal and petroleum often contain sulfur compounds, and their combustion generates sulfur dioxide. Further oxidation of SO2, usually in the presence of a catalyst such as NO2, forms H2. SO4, and thus acid rain. They can be seen as a brown haze dome above or a plume downwind of cities. Nitrogen dioxide is a chemical compound with the formula NO2. It is one of several nitrogen oxides. One of the most prominent air pollutants, this reddish- brown toxic gas has a characteristic sharp, biting odor. Carbon monoxide (CO) - CO is a colorless, odorless, toxic yet non- irritating gas. It is a product by incomplete combustion of fuel such as natural gas, coal or wood. Vehicular exhaust is a major source of carbon monoxide. Volatile organic compounds (VOC) - VOCs are a well- known outdoor air pollutant. They are categorized as either methane (CH4) or non- methane (NMVOCs). Methane is an extremely efficient greenhouse gas which contributes to enhanced global warming. Other hydrocarbon VOCs are also significant greenhouse gases because of their role in creating ozone and prolonging the life of methane in the atmosphere. This effect varies depending on local air quality. The aromatic NMVOCs benzene, toluene and xylene are suspected carcinogens and may lead to leukemia with prolonged exposure. Particulates, alternatively referred to as particulate matter (PM), atmospheric particulate matter, or fine particles, are tiny particles of solid or liquid suspended in a gas. In contrast, aerosol refers to combined particles and gas. Some particulates occur naturally, originating from volcanoes, dust storms, forest and grassland fires, living vegetation, and sea spray. Human activities, such as the burning of fossil fuels in vehicles, power plants and various industrial processes also generate significant amounts of aerosols. Averaged worldwide, anthropogenic aerosols. Increased levels of fine particles in the air are linked to health hazards such as heart disease. These are gases which are released from air conditioners, refrigerators, aerosol sprays, etc. CFC's on being released into the air rises to stratosphere. Here they come in contact with other gases and damage the ozone layer. This allows harmful ultraviolet rays to reach the earth's surface. This can lead to skin cancer, disease to eye and can even cause damage to plants. Ammonia (NH3) - emitted from agricultural processes. Ammonia is a compound with the formula NH3. It is normally encountered as a gas with a characteristic pungent odor. Ammonia contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to foodstuffs and fertilizers. Ammonia, either directly or indirectly, is also a building block for the synthesis of many pharmaceuticals. Although in wide use, ammonia is both caustic and hazardous. In the atmosphere, ammonia reacts with oxides of nitrogen and sulfur to form secondary particles. Smog is a kind of air pollution. Classic smog results from large amounts of coal burning in an area caused by a mixture of smoke and sulfur dioxide. Modern smog does not usually come from coal but from vehicular and industrial emissions that are acted on in the atmosphere by ultraviolet light from the sun to form secondary pollutants that also combine with the primary emissions to form photochemical smog. Ground level ozone (O3) formed from NOx and VOCs. Ozone (O3) is a key constituent of the troposphere. It is also an important constituent of certain regions of the stratosphere commonly known as the Ozone layer. Photochemical and chemical reactions involving it drive many of the chemical processes that occur in the atmosphere by day and by night. At abnormally high concentrations brought about by human activities (largely the combustion of fossil fuel), it is a pollutant, and a constituent of smog. Peroxyacetyl nitrate (PAN) - similarly formed from NOx and VOCs. Minor air pollutants include: Persistent organic pollutants (POPs) are organic compounds that are resistant to environmental degradation through chemical, biological, and photolytic processes. Because of this, they have been observed to persist in the environment, to be capable of long- range transport, bioaccumulate in human and animal tissue, biomagnify in food chains, and to have potentially significant impacts on human health and the environment. Sources. This video provides an overview of a NASA study on the human fingerprint on global air quality. There are various locations, activities or factors which are responsible for releasing pollutants into the atmosphere. These sources can be classified into two major categories. Anthropogenic (man- made) sources: These are mostly related to the burning of multiple types of fuel. Stationary sources include smoke stacks of power plants, manufacturing facilities (factories) and waste incinerators, as well as furnaces and other types of fuel- burning heating devices. In developing and poor countries, traditional biomass burning is the major source of air pollutants; traditional biomass includes wood, crop waste and dung. Controlled or prescribed burning is a technique sometimes used in forest management, farming, prairie restoration or greenhouse gas abatement. Fire is a natural part of both forest and grassland ecology and controlled fire can be a tool for foresters. Controlled burning stimulates the germination of some desirable forest trees, thus renewing the forest. Fumes from paint, hair spray, varnish, aerosol sprays and other solvents. Waste deposition in landfills, which generate methane. Methane is highly flammable and may form explosive mixtures with air. Methane is also an asphyxiant and may displace oxygen in an enclosed space. Asphyxia or suffocation may result if the oxygen concentration is reduced to below 1. Military resources, such as nuclear weapons, toxic gases, germ warfare and rocketry. Natural sources: Dust from natural sources, usually large areas of land with little or no vegetation. Methane, emitted by the digestion of food by animals, for example cattle. Radon gas from radioactive decay within the Earth's crust. Radon is a colorless, odorless, naturally occurring, radioactive noble gas that is formed from the decay of radium. It is considered to be a health hazard. Radon gas from natural sources can accumulate in buildings, especially in confined areas such as the basement and it is the second most frequent cause of lung cancer, after cigarette smoking. Smoke and carbon monoxide from wildfires. Vegetation, in some regions, emits environmentally significant amounts of Volatile organic compounds (VOCs) on warmer days. These VOCs react with primary anthropogenic pollutants. The VOC production from these species result in ozone levels up to eight times higher than the low- impact tree species. These factors are usually expressed as the weight of pollutant divided by a unit weight, volume, distance, or duration of the activity emitting the pollutant (e. Such factors facilitate estimation of emissions from various sources of air pollution. In most cases, these factors are simply averages of all available data of acceptable quality, and are generally assumed to be representative of long- term averages. There are 1. 2 compounds in the list of persistent organic pollutants. Dioxins and furans are two of them and intentionally created by combustion of organics, like open burning of plastics. These compounds are also endocrine disruptors and can mutate the human genes. The United States Environmental Protection Agency has published a compilation of air pollutant emission factors for a multitude of industrial sources. Air pollution exposure can be expressed for an individual, for certain groups (e. For example, one may want to calculate the exposure to a hazardous air pollutant for a geographic area, which includes the various microenvironments and age groups. This can be calculated. This would account for daily exposure in various settings (e. The exposure needs to include different age and other demographic groups, especially infants, children, pregnant women and other sensitive subpopulations. The exposure to an air pollutant must integrate the concentrations of the air pollutant with respect to the time spent in each setting and the respective inhalation rates for each subgroup for each specific time that the subgroup is in the setting and engaged in particular activities (playing, cooking, reading, working, etc.).
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