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Air quality monitors are operated by citizens, [3] [4] [5] regulatory agencies, [6] [7] non-governmental organisations [8] and researchers [9] to investigate air quality and the effects of air pollution. Interpretation of ambient air monitoring data often involves a consideration of the spatial and temporal representativeness [10] of the data ...
The European Environment Agency collects its air quality data from 3,500 monitoring stations across the continent. [24] The measurements made by sensors like these, which are much more accurate, are also near real-time and are used to generate air quality indexes (AQIs). Between the two extremes of large-scale static and small-scale wearable ...
Modern particulate samplers use a volumetric flow control system that pulls air through the particle separator at the velocity required to achieve the desired cutpoint. For air pollution applications, the definition of "particulate" does not include uncombined water , and water from a particulate sample must be removed before it is weighed.
Diffusion tubes are widely used by local authorities for monitoring air quality in urban areas, [2] in citizen science pollution-monitoring projects carried out by community groups and schools, [3] [4] and in indoor environments such as mines [5] and museums. [6]
Some air pollution laws include specific air quality standards, such as the U.S. National Ambient Air Quality Standards and E.U. Air Quality Directive, [276] which specify maximum atmospheric concentrations for specific pollutants. Environmental agencies enact regulations which are intended to result in attainment of these target levels.
Ambient air quality criteria, or standards, are concentrations of pollutants in the air, and typically refer to outdoor air.The criteria are specified for a variety of reasons including for the protection of human health, buildings, crops, vegetation, ecosystems, as well as for planning and other purposes.
CEM systems can also measure air flow, flue gas opacity and moisture. A monitoring system that measures particulate matter is referred to as a PEMS. In the U.S., the EPA requires a data acquisition and handling system to collect and report the data. Measurements of concentration can be converted to mass/hour by including flow rate measurements.
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]