Is ground level ozone a primary or secondary pollutant?
Ozone, unlike the other criteria pollutants, is not emitted directly into the air by any one source. Ground-level ozone is a secondary pollutant. It is formed through chemical reactions of other molecules already in the air, specifically nitrogen oxides (NOx) and volatile organic compounds (VOCs).
Is ground level ozone a pollutant?
Ozone at ground level is a harmful air pollutant, because of its effects on people and the environment, and it is the main ingredient in “smog.” Learn more about air emission sources.
What ground level air pollution is ozone a major component of?
photochemical smog
Ozone irritates people’s lungs and is a major component of photochemical smog. Ground level ozone gives photochemical smog its unpleasant odor and can cause lung function complications, especially in young children.
What does ground level ozone come from?
Ground-level ozone comes from pollution emitted from cars, power plants, industrial boilers, refineries, and chemical plants. Ozone pollution can even come from paints, cleaners, solvents, and motorized lawn equipment.
Why is ground level ozone said to be a secondary pollutant?
Ground-level ozone is a colorless and highly irritating gas that forms just above the earth’s surface. It is called a “secondary” pollutant because it is produced when two primary pollutants react in sunlight and stagnant air. These two primary pollutants are nitrogen oxides (NOx) and volatile organic compounds (VOCs).
What are secondary pollutants?
Secondary pollutants are pollutants which form in the atmosphere. These pollutants are not emitted directly from a source (like vehicles or power plants). Photochemical smog is made up of various secondary pollutants like ozone, peroxyacyl nitrates (PANs), and nitric acid (seen in Figure 2).
What is ground level ozone pollution?
What is primary pollutant O3?
Ozone (O3) is a colorless gas made up of three oxygen atoms. In the upper atmosphere, ozone exists naturally and shields the earth from the sun’s ultraviolet rays. Near the ground, however, ozone is a pollutant and the primary component of summertime smog.
How is ozone formed from a primary pollutants?
Tropospheric or ground-level ozone – what we breathe – is formed primarily from photochemical reactions between two major classes of air pollutants, volatile organic compounds (VOC) and nitrogen oxides (NOx).
What is a primary pollutant?
A primary pollutant is an air pollutant emitted directly from a source. A secondary pollutant is not directly emitted as such, but forms when other pollutants (primary pollutants) react in the atmosphere.
Why is ground level ozone considered a secondary pollutant?
Common air pollutants: ground-level ozone. Ground-level ozone is a colorless and highly irritating gas that forms just above the earth’s surface. It is called a “secondary” pollutant because it is produced when two primary pollutants react in sunlight and stagnant air.
Which is the most common secondary pollutant in the air?
Common air pollutants: ground-level ozone. It is called a “secondary” pollutant because it is produced when two primary pollutants react in sunlight and stagnant air. These two primary pollutants are nitrogen oxides (NOx) and volatile organic compounds (VOCs). NOx and VOCs come from natural sources as well as human activities.
What are the rules for ground level ozone?
EPA’s national and regional rules to reduce emissions of pollutants that form ground level ozone will help state and local governments meet the Agency’s national air quality standards. Actions include vehicle and transportation standards, regional haze and visibility rules, and regular reviews of the NAAQS.
What causes the level of ozone to be high?
This happens when pollutants emitted by cars, power plants, industrial boilers, refineries, chemical plants, and other sources chemically react in the presence of sunlight. Ozone is most likely to reach unhealthy levels on hot sunny days in urban environments, but can still reach high levels during colder months.