Page 255 - Fundamentals of Air Pollution

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Air Pollution Monitoring

and Surveillance

I. STATIONARY MONITORING NETWORKS

The U.S. Environmental Protection Agency has established National Am-
bient Air Quality Standards (NAAQS) for protection of human health and
welfare. These standards are defined in terms of concentration and time
span for a specific pollutant; for example, the NAAQS for carbon monoxide
is 9 ppmV for 8 hr, not to be exceeded more than once per year. For a state
or local government to establish compliance with a National Ambient Air
Quality Standard, measurements of the actual air quality must be made. To
obtain these measurements, state and local governments have established
stationary monitoring networks with instrumentation complying with fed-
eral specifications, as discussed in Chapter 14. The results of these measure-
ments determine whether a given location is violating the air quality
standard.
Stationary monitoring networks are also operated to determine the impact
of new sources of emissions. As part of the environmental impact statement
and Prevention of Significant Deterioration processes, the projected impact
of a new source on existing air quality must be assessed. Air quality monitor-
ing is one means of making this type of assessment. A monitoring network

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