National Ambient Air Quality
Standards (NAAQS)
The United States Environmental Protection Agency
(EPA) is responsible for establishing and maintaining the NAAQS to protect
health and welfare. Primary NAAQS are designed to protect the public health
and secondary standards are designed to protect public welfare including
the effects of air pollution on visibility, materials and vegetation.
NAAQS have been established for the following pollutants:
Ozone - Ozone (O3) is
a colorless and highly unstable molecular form of oxygen that is associated
with the presence of photochemical smog. Ozone is not emitted directly
into the air from any source. Instead, it is formed by chemical reactions
involving volatile organic compounds (VOC’s) and oxides of nitrogen
(NOX) in the presence of sunlight. NOX is emitted from sources of high
temperature combustion. VOC’s are emitted primarily from transportation
sources such as cars and trucks. (For
additional information on Ozone) 
Carbon Monoxide
- Carbon monoxide
(CO) is a by-product of the incomplete combustion of fuels. Transportation
related sources account for over 98% of all CO pollution in the county.
(For
additional information on Carbon Monoxide)
Sulfur Dioxide
- Sulfur Dioxide (SO2) is emitted primarily
from steam power and steam-electric power generating facilities that consume
sulfur containing fossil fuel such as coal and oil. (For
additional information on Sulfur Dioxide)
Nitrogen Dioxide
- Much of the nitrogen dioxide (NO2) in the
atmosphere is formed from nitrogen oxide (NO) released during high temperature
combustion of fuels. Primary sources of NO and NO2 are coal and oil fired
electric utility boilers and transportation sources such as gasoline and
diesel powered cars, trucks, and buses. (For
additional information on Nitrogen Dioxide)
Particulate Matter
- The characteristics
and sources of larger or “coarse” particles (from 2.5 to 10
micrometers in diameter) and smaller or “fine” particles (smaller
than 2.5 micrometers in diameter) are very different. Coarse particles
(PM10) come from sources such as windblown dust from agricultural fields,
grinding operations, and dust kicked up on unpaved roads by vehicular
traffic. Fine particles (PM2.5) are generally emitted from activities
such as industrial and residential combustion, open burning of trash and
garbage, and from vehicle exhaust. Fine particles are also formed in the
atmosphere when gases such as sulfur dioxide, nitrogen oxides, and volatile
organic compounds, emitted by combustion activities, are transformed by
chemical reactions in the air. (For
additional information on Particulate Matter)
Lead
- Lead (Pb) is primarily emitted from sources
such as nonferrous smelters, battery plants and lead gasoline additives. Children
are more sensitive to the effects of lead than adults. However, studies
have shown that levels of lead in the blood of children in the United
States has been getting lower each year due to lead being banned from
gasoline, residential paint, and solder used in cans and water pipes.
Depending on how much lead a child ingests, it may cause anemia, kidney
damage, muscle weakness and neurological damage. Low levels may affect
a child’s mental and physical growth. Exposure can be assessed with
a blood sample or x-ray of bones. (For
additional information on Lead)
Hazardous Air Pollutants - Numerous toxic
or hazardous air pollutants (HAP's) are now regulated on both a regional
and national level. Sources for these pollutants include a wide variety
of industrial and agricultural processes. To date there are approximately
190 hazardous air pollutants being considered for regulation. (For
additional information on Hazardous Air Pollutants)
Air
Quality Index -- Real-Time Air Quality Data
The air quality index (AQI) is a nationwide standard method developed
by the EPA for reporting daily air quality to the public in a health-related
manner. It tells you how clean your air is, and what associated health
concerns you should be aware of. The AQI describes ambient air quality
concentration levels for sulfur dioxide, ozone, carbon monoxide, nitrogen
dioxide, and particulate matter in terms of a concentration index for
the highest pollutant level in a previous time period. The pollutant concentrations
are measured and converted to numbers based on a mathematical formula
that transforms ambient pollutant concentrations onto a scale where an
AQI of 100 would be equal to the National Ambient Air Quality Standard.
Pinellas
County Air Quality Division (AQD) makes an Air Quality
Forecast for the current and next day each Monday
through Friday
(except holidays). The initial forecast is made by 11
am and is updated as needed at approximately 4:00 pm
and is available
from the following sources:
Phone:
(727) 464-3392
Local Air Quality
Status
In
1991, Pinellas County was declared to be marginal
non-attainment for ozone. Two major precursors
(pollutants that contribute to the formation
of ozone in the atmosphere) were identified
as Volatile Organic Compounds (VOC’s)
and Oxides of Nitrogen (NOX). By 1996, the
emission levels of these pollutants had been
reduced such that Pinellas County was in attainment
for the ozone standard and the county was reclassified
as a maintenance area. This means that for
a twenty year period, emissions of these pollutants
must not exceed levels established in a statewide
emissions plan (Florida
State Implementation Plan) .
At this time, Pinellas County continues to comply with
the standards for all of the criteria pollutants including
the new 8-hour ozone standard (3-year average
of 4th high).
Check out the following
for information on local and national air quality data, the Air Quality
index, and other monitoring information:
(
Indicates
PDF file)
