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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 agents ...
A pollutant or novel entity [1] is a substance or energy introduced into the environment that has undesired effects, or adversely affects the usefulness of a resource. These can be both naturally forming (i.e. minerals or extracted compounds like oil) or anthropogenic in origin (i.e. manufactured materials or byproducts ).
Pollution is the introduction of contaminants into the natural environment that cause adverse change. [1] Pollution can take the form of any substance (solid, liquid, or gas) or energy (such as radioactivity, heat, sound, or light). Pollutants, the components of pollution, can be either foreign substances/energies or naturally occurring ...
An air quality index ( AQI) is an indicator developed by government agencies [1] to communicate to the public how polluted the air currently is or how polluted it is forecast to become. [2] [3] As air pollution levels rise, so does the AQI, along with the associated public health risk. Children, the elderly and individuals with respiratory or ...
History Initial petition and initial denial. Section 202(a)(1) of the Clean Air Act requires the Administrator of the EPA to establish standards "applicable to the emission of any air pollutant from…new motor vehicles or new motor vehicle engines, which in [her] judgment cause, or contribute to, air pollution which may reasonably be anticipated to endanger public health or welfare" (emphasis ...
Regulation of air pollution is a shared responsibility between federal, state, and local governments. Since 1999, the EPA has used the air quality index (AQI) to communicate air pollution risk to the public, on a scale from 0 to 500, with six levels from Good to Hazardous. [11] (.
National Ambient Air Quality Standards. US counties that are designated "nonattainment" for the Clean Air Act's NAAQS, as of September 30, 2017. The U.S. National Ambient Air Quality Standards ( NAAQS, pronounced / ˈnæks / naks) are limits on atmospheric concentration of six pollutants that cause smog, acid rain, and other health hazards. [1]
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 and dust collectors known as deposit gauges . [1]