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  2. United States vehicle emission standards - Wikipedia

    en.wikipedia.org/wiki/United_States_vehicle...

    The Clean Air Act of 1963 (CAA) was passed as an extension of the Air Pollution Control Act of 1955, encouraging the federal government via the United States Public Health Service under the then-Department of Health, Education, and Welfare (HEW) to encourage research and development towards reducing pollution and working with states to establish their own emission reduction programs.

  3. Air pollution in the United States - Wikipedia

    en.wikipedia.org/wiki/Air_pollution_in_the...

    Looking down from the Hollywood Hills, with Griffith Observatory on the hill in the foreground, air pollution is visible in downtown Los Angeles on a late afternoon.. Air pollution is the introduction of chemicals, particulate matter, or biological materials into the atmosphere, causing harm or discomfort to humans or other living organisms, or damaging ecosystems.

  4. Air pollution measurement - Wikipedia

    en.wikipedia.org/wiki/Air_pollution_measurement

    Air quality monitoring sensors in Port Pirie, South Australia. Air pollution measurement is the process of collecting and measuring the components of air pollution, notably gases and particulates. The earliest devices used to measure pollution include rain gauges (in studies of acid rain), Ringelmann charts for measuring smoke, and simple soot ...

  5. Air pollution - Wikipedia

    en.wikipedia.org/wiki/Air_pollution

    e. Air pollution is the contamination of air due to the presence of substances called pollutants in the atmosphere that are harmful to the health of humans and other living beings, or cause damage to the climate or to materials. [ 1 ] It is also the contamination of the indoor or outdoor environment either by chemical, physical, or biological ...

  6. August Wilson - Wikipedia

    en.wikipedia.org/wiki/August_Wilson

    August Wilson (né Frederick August Kittel Jr.; April 27, 1945 – October 2, 2005) was an American playwright. He has been referred to as the "theater's poet of Black America". [ 1 ] He is best known for a series of 10 plays, collectively called The Pittsburgh Cycle (or The Century Cycle ) , which chronicle the experiences and heritage of the ...

  7. Ringelmann scale - Wikipedia

    en.wikipedia.org/wiki/Ringelmann_scale

    The Ringelmann scale is a scale for measuring the apparent density or opacity of smoke. [1][2] It was developed by a French professor of agricultural engineering Maximilien Ringelmann of La Station d'Essais de Machines in Paris, who first specified the scale in 1888. [3][4] The scale has 5 levels of density inferred from a grid of black lines ...

  8. AP 42 Compilation of Air Pollutant Emission Factors - Wikipedia

    en.wikipedia.org/wiki/AP_42_Compilation_of_Air...

    Air pollution emission factors are usually expressed as the weight of the pollutant divided by a unit weight, volume, distance, or duration of the activity emitting the pollutant (e.g., kilograms of particulate matter emitted per megagram of coal burned). The factors help to estimate emissions from various sources of air pollution.

  9. Outline of air pollution dispersion - Wikipedia

    en.wikipedia.org/wiki/Outline_of_air_pollution...

    The following outline is provided as an overview of and topical guide to air pollution dispersion: In environmental science, air pollution dispersion is the distribution of air pollution into the atmosphere. Air pollution is the introduction of particulates, biological molecules, or other harmful materials into Earth's atmosphere, causing ...