Criteria pollutants are air pollutants which, at certain levels of exposure, do not threaten human health and meet National Ambient Air Quality Standards. There are two types of standards for such pollutants. National primary ambient air quality standards are levels of air quality with a margin of safety adequate to protect public health. National secondary ambient air quality standards are levels of air quality which are necessary to protect the public welfare from any known or anticipated adverse effects of a pollutant.

See Also

Air Quality Control Region; Air Quality Criteria; Primary Standards; Secondary Standards