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The reports provide guidelines intending to give guidelines to reduce the health effects of air pollution. [2] 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]
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 cardiopulmonary mortality rate by 6-13%. [35] Worldwide, PM 10 concentrations of 70 μg/m 3 and PM 2.5 concentrations of 35 μg/m 3 have been shown to increase long-term ...
The six criteria air pollutants were the first set of pollutants recognized by the United States Environmental Protection Agency as needing standards on a national level. [5] The Clean Air Act requires the EPA to set US National Ambient Air Quality Standards (NAAQS) for the six CAPs. [6]
A separate Year Average Common Air Quality Index (YACAQI) is also defined, in which different pollutant sub-indices are separately normalised to a value typically near unity. For example, the yearly averages of NO 2, PM 10 and PM 2.5 are divided by 40 μg/m 3, 40 μg/m 3 and 20 μg/m 3, respectively.
Directive 2008/50/EC, or the Ambient Air Quality Directive, is an EU directive which limits sulphur dioxide, NO 2 and other oxides of nitrogen, particulate matter (PM10, PM2.5), lead, benzene and carbon monoxide concentrations from 2010.
Particulates or atmospheric particulate matter (see below for other names) are microscopic particles of solid or liquid matter suspended in the air.The term aerosol refers to the particulate/air mixture, as opposed to the particulate matter alone, [1] though it is sometimes defined as a subset of aerosol terminology. [2]
To discriminate between particle of different sizes (e. g., between PM 10 and PM 2.5), some preliminary separation could be accomplished, for example, by cyclone battery. A similar method exists, where instead of beta particle flow an X-ray Fluorescence Spectroscopic monitoring is applied on the either side of air flow contact with the ribbon.
As an example, a measured NO x concentration of 45 ppmv in a dry gas having 5 volume % O 2 is: 45 × ( 20.9 - 3 ) ÷ ( 20.9 - 5 ) = 50.7 ppmv of NO x. when corrected to a dry gas having a specified reference O 2 content of 3 volume %. Note: The measured gas concentration C m must first be corrected to a dry basis before using the above equation.