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

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

    This list contains the top 500 cities by PM2.5 annual mean concentration measurement as documented by the World Health Organization covering the period from 2010 to 2022. The January 2024 version of the WHO database contains results of ambient (outdoor) air pollution monitoring from almost 5,390 towns and cities in 63 countries.

  3. Particulate pollution - Wikipedia

    en.wikipedia.org/wiki/Particulate_pollution

    However, there is no known safe level of exposure and thus, any exposure to particulate pollution is likely to increase an individual's risk of adverse health effects. [35] In European countries, air quality at or above 10 micrograms per cubic meter of air (μg/m 3 ) for PM 2.5 increases the all-causes daily mortality rate by 0.2-0.6% and the ...

  4. Air quality index - Wikipedia

    en.wikipedia.org/wiki/Air_quality_index

    The index is defined in both hourly and daily versions, and separately near roads (a "roadside" or "traffic" index) or away from roads (a "background" index). As of 2012, the CAQI had two mandatory components for the roadside index, NO 2 and PM 10, and three mandatory components for the background index, NO 2, PM 10 and O 3.

  5. List of countries by air pollution - Wikipedia

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

    Rank Country Particulate matter ((in μg/m 3) WHO-Guideline=5 Loss of life expectancy (years) 1 Bangladesh 54.17 −4.82 2 India 41.39 −3.57 3 Nepal 39.18 −3.32 4

  6. Particulates - Wikipedia

    en.wikipedia.org/wiki/Particulates

    On the other hand, Omaha, Nebraska is performing the best and has a decrease of −1.1 μg/m 3 in PM 2.5 levels. The cleanest city in this report is Zürich, Switzerland with PM 2.5 levels of just 0.5 μg/m 3, placed first in both 2019 and 2022. The second cleanest city is Perth, with 1.7 μg/m 3 and PM 2.5 levels dropping by −6.2 μg/m 3 since

  7. National Ambient Air Quality Standards - Wikipedia

    en.wikipedia.org/wiki/National_Ambient_Air...

    In April 2001, the EPA created a Second External Review Draft of the Air Quality Criteria for PM, which addressed updated studies done on particulate matter and the modified pollutant standards done since the First External Review Draft. In May 2002, a Third External Review Draft was made, and the EPA revised PM requirements again.

  8. Air quality guideline - Wikipedia

    en.wikipedia.org/wiki/Air_quality_guideline

    The guidelines stipulate that PM 2.5 should not exceed 5 μg/m 3 annual mean, or 15 μg/m 3 24-hour mean; and that PM 10 should not exceed 15 μg/m 3 annual mean, or 45 μg/m 3 24-hour mean. [2] For ozone (O 3 ), the guidelines suggest values no higher than 100 μg/m 3 for an 8-hour mean and 60 μg/m 3 peak season mean. [ 2 ]

  9. Pollutant Standards Index - Wikipedia

    en.wikipedia.org/wiki/Pollutant_Standards_Index

    The Pollutant Standards Index (PSI) is a type of air quality index used in Singapore, which is a number used to indicate the level of pollutants in air.Initially PSI was based on five air pollutants, but since 1 April 2014 it has also included fine particulate matter (PM 2.5).