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Particulate pollution is observed around the globe in varying sizes and compositions and is the focus of many epidemiological studies. Particulate matter (PM) is generally classified into two main size categories: PM 10 and PM 2.5.
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]
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.
Annual seasonal average particulate matter concentrations have been recorded as high as 279 μg/m 3 (micrograms per cubic meter). [citation needed] The World Health Organization's recommended annual mean PM 10 level is 20 μg/m 3, [296] which means that Ulaanbaatar's PM 10 annual mean levels are 14 times higher than recommended. [citation needed]
The following list of countries by air pollution sorts the countries of the world according to their average measured concentration of particulate matter in micrograms per cubic meter (μg/m 3). The World Health Organization's recommended limit is 10 micrograms per cubic meter, although there are also various national guideline values, which ...
Atmospheric particulate matter. PM 10, coarse particles: 2.5 micrometers (μm) to 10 μm in size (although current implementation includes all particles 10 μm or less in the standard) PM 2.5, fine particles: 2.5 μm in size or less. Particulate Matter (PM) was listed in the 1996 Criteria document issued by the EPA.
This index, reported by the Environmental Protection Department, is measured on a scale of 1 to 10+ and considers four air pollutants: ozone; nitrogen dioxide; sulfur dioxide and particulate matter (including PM10 and PM2.5). For any given hour the AQHI is calculated from the sum of the percentage excess risk of daily hospital admissions ...
The National Ambient Air Quality Standards (NAAQS) govern how much ground-level ozone (O 3), carbon monoxide (CO), particulate matter (PM 10, PM 2.5), lead (Pb), sulfur dioxide (SO 2), and nitrogen dioxide (NO 2) are allowed in the outdoor air. [6] The NAAQS set the acceptable levels of certain air pollutants in the ambient air in the United ...