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  2. 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 ...

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

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

    History. The AP 42 Compilation of Air Pollutant Emission Factors is a compilation of emission factors of air pollutants, in other words numbers which relate the quantity of a pollutant released into the ambient air with a certain activity. This compilation was first compiled and published by the US Public Health Service in 1968.

  4. 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.

  5. Air quality index - Wikipedia

    en.wikipedia.org/wiki/Air_quality_index

    An air quality index (AQI) is an indicator developed by government agencies [1] to communicate to the public how polluted the air currently is or how polluted it is forecast to become. [2][3] As air pollution levels rise, so does the AQI, along with the associated public health risk. Children, the elderly and individuals with respiratory or ...

  6. Ringelmann scale - Wikipedia

    en.wikipedia.org/wiki/Ringelmann_scale

    Ringelmann smoke charts, 1897. 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.

  7. Air pollutant concentrations - Wikipedia

    en.wikipedia.org/wiki/Air_pollutant_concentrations

    Correcting concentrations for altitude. Air pollutant concentrations expressed as mass per unit volume of atmospheric air (e.g., mg/m 3, μg/m 3, etc.) at sea level will decrease with increasing altitude. The concentration decrease is directly proportional to the pressure decrease with increasing altitude.

  8. 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.

  9. 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 ...