The Clean Air Act, which was last amended in 1990, requires the USEPA to set National Ambient Air Quality Standards (NAAQS) for wide-spread pollutants from numerous and diverse sources considered harmful to public health and the environment. Some sources of air pollution include aircraft, automobiles, industrial operations, and power plants. The Clean Air Act established two types of national air quality standards. Primary standards set limits to protect public health, including the health of "sensitive" populations such as asthmatics, children, and the elderly. Secondary standards set limits to protect public welfare, including protection against visibility impairment, damage to animals, crops, vegetation, and buildings.

The USEPA has set NAAQS for six principal pollutants, which are called "criteria" pollutants. They are carbon monoxide, lead, nitrogen dioxide, ozone, particulate matter, and sulfur dioxide.

In an ongoing effort to evaluate compliance with federal and state air quality standards, most states establish networks of individual monitor sites to provide real-time monitoring of air pollution episodes. Air quality monitoring data collected is used for trend analysis, for developing and implementing air quality regulations, and for providing information to the public on daily air quality conditions in their area.

Avogadro air quality scientist and engineers provide ambient air quality monitoring services for all criteria pollutants and specific air toxics.

Avogadro has proven experience in a variety of ambient air quality monitoring projects including:

• Environmental Impact Statements (EIS)
• Intercomparison Studies
• New Source Review (NSR)
• Pre-construction Monitoring Activities
• Prevention of Significant Deterioration (PSD)
• Source Attribution Studies
• Upwind / Downwind Studies