| definition |
- Between the years 1900 and 1970, the emission of six principal pollutants
increased significantly. These six pollutants, also called criteria pollutants,
are: particulate matter, sulfur dioxide, carbon monoxide, nitrogen dioxide,
ozone, and lead. In 1970, the Clean Air Act (CAA) was signed into law. The CAA
and its amendments provides the framework for all pertinent organizations to
protect air quality.
One way to protect and assess air quality was through the development of an
Ambient Air Monitoring Program. Air quality samples are generally collected for
one or more of the following purposes:
* To judge compliance with and/or progress made towards meeting ambient air
quality standards.
* To activate emergency control procedures that prevent or alleviate air
pollution episodes.
* To observe pollution trends throughout the region, including non-urban areas.
* To provide a data base for research evaluation of effects: urban, land-use,
and transportation planning; development and evaluation of abatement
strategies; and development and validation of diffusion models.
The EPA's ambient air quality monitoring program is carried out by State and
local agencies and consists of three major categories of monitoring stations,
State and Local Air Monitoring Stations (SLAMS), National Air Monitoring
Stations (NAMS), and Special Purpose Monitoring Stations (SPMS), that measure
the criteria pollutants. Additionally, a fourth category of a monitoring
station, the Photochemical Assessment Monitoring Stations (PAMS), which
measures ozone precursors (approximately 60 volatile hydrocarbons and carbonyl)
has been required by the 1990 Amendments to the Clean Air Act.
[Source: "http://www.epa.gov/air/oaqps/qa/monprog.html"]
|
