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stream parameters must be recalculated using a standard industrial equation when the
temperature of the gas stream is preheated, because when the gas stream temperature
increases, it increases the actual gas flow rate of the emission stream.

9. AIR QUALITY MANAGEMENT
9.1. Recent Focus
9.1.1. Emission Sources
A recent focus of air quality management (12,18–61) has been on reducing natural and
man-made airborne contaminants from various sources: (1) point source hazardous air
emissions, (2) non-point-source fugitive hazardous emissions, (3) greenhouse or global
warming gases, (4) ozone-depleting gases, (5) indoor emissions that release asbestos,
microorganisms, radon gases, VOCs, lead, and so forth, (6) odor emissions, (7) vehicle
emissions, (8) wildfire emissions, and (9) terrorists’ emissions of airborne infectious
and/or toxic contaminants.
In this handbook, the chapters entitled “Fabric Filtration,” “Cyclones,” “Electrostatic
Precipitation,” “Web and Dry Scrubbing,” “Condensation,” “Flare Process,” “Thermal
Oxidation,” “Catalytic Oxidation,” “Gas-Phase Carbon Adsorption,” and “Gas-Phase
Biofiltration” introduce the new technologies for removal of the point source hazardous air
emissions in detail. Another chapter, “Emerging Air Pollution Control Technologies,”
introduces various new technologies for the treatment of non-point-sources fugitive haz-
ardous emissions and vehicle emissions.
Indoor and odor pollution problems are addressed in detail in the chapters entitled
“Ventilation and Air Conditioning,” “Indoor Air Pollution Control,” “Noise Pollution,”
and “Noise Control.” Additional literature of indoor and odor pollution control can be
found elsewhere (39–43,59).
Discussions of the greenhouse or global warming gases, and the ozone-depleting
gases are covered in Sections 9.2 and 9.4. The readers are also referred to a chapter
entitled “Carbon Sequestration” in ref. 59.
Terrorist-launched emissions of airborne biocontaminants and toxic gases cannot be
prevented nor controlled easily and cost-effectively (49–53). Rademakers (49) intro-
duced the biological warfare detection technologies and new decontamination methods.
Ziegler (50) introduced the procedures to deal with a terrorist incident emitting airborne
pathogenic microorganisms or toxic gases. Gudia (51) presented an overview of issues
related to environmental regulations as we attempt to deal with possible future terrorist
events. Abkowitz (52) raised communication issues related to dealing with possible
future emergencies.
As stated previously, lightning is the main cause of producing bad ozone in the tro-
pospheric zone and is also the indirect cause of large amounts of combustion-related air
pollution as a result of forest fires. In the United States alone, there are over 10,000 for-
est fires annually, which are mainly caused by lightning. Natural air pollution sources,
such as volcanic eruptions and forest fires, produce much more airborne pollutants than
all man-made airborne pollutants combined. Although we have no control over volcanic
eruptions, perhaps attention should be paid to management of forest fires. In January
2003, the United States government proposed steps to prevent wildfires (62).