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  2. 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 ...

  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. 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.

  6. List of countries by air pollution - Wikipedia

    en.wikipedia.org/wiki/List_of_countries_by_air...

    Air pollution can affect nearly every organ and system of the body, negatively affecting nature and humans alike. Air pollution is a particularly big problem in emerging and developing countries, where global environmental standards often cannot be met. The data in this list refers only to outdoor air quality and not indoor air quality, which ...

  7. Air quality guideline - Wikipedia

    en.wikipedia.org/wiki/Air_quality_guideline

    The World Health Organization guidelines were most recently updated in 2021. [1] The guidelines offer guidance about these air pollutants: particulate matter (PM), ozone (O 3), nitrogen dioxide (NO 2), sulfur dioxide (SO 2) and carbon monoxide (CO). [2] The WHO first released the air quality guidelines in 1987, then updated them in 1997. [2]

  8. List of most-polluted cities by particulate matter concentration

    en.wikipedia.org/wiki/List_of_most-polluted...

    The 2018 version of the WHO database contains results of ambient (outdoor) air pollution monitoring from almost 2700 towns and cities in 91 countries. Air quality in the database is represented by the annual mean concentration of particulate matter (PM10 and PM2.5, i.e. particles smaller than 10 or 2.5 micrometers, respectively). [1] [2] [3]

  9. 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.