Primary air pollutants

What are primary and secondary pollutants? Are secondary pollutants more harmful than primary pollutants? Primary air pollutants (PAPs) are those that are emitted directly into the air from sources. Examples – Sulphur dioxide, nitrogen oxides, carbon monoxide, volatile organic matter, particulate matters, lea ammonia etc.

The Clean Air Act requires EPA to set National Ambient Air Quality Standards (NAAQS) National Ambient Air Quality StandardsNational Ambient Air Quality Standards established by EPA for six criteria pollutants in outdoor air. NAAQS are currently set for carbon monoxide, lea ground-level ozone, nitrogen dioxide, particulate matter, and sulfur. 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. Major examples of secondary pollutants are photochemical oxidants and secondary particulate matter. Various Causes of Air Pollution Air pollution is the introduction of harmful substances in the air that have detrimental impacts to the environment and humanity.

It occurs when the harmful substances such as foreign gases, odour, dust, or fumes are present in the air at levels that can harm the comfort and health of animals and humans or even. NOx for example is emitted from vehicles and power plants, yet it can also form in the atmosphere from other chemicals. Compare and contrast primary vs.

When considering primary pollutants , the main source for them is the motor vehicles. Fossil fuel burning releases a mixture of primary pollutants. Primary pollutants can also be precursors for the secondary pollutants. Secondary pollutants are not emitted directly. Rather, they form in the air when primary pollutants react or interact.

Ground level ozone is a prominent example of secondary pollutants. Some pollutants may be both primary and secondary: they are both emitted directly and formed from other primary pollutants. Sulfur dioxide is a gas. It is invisible and has a nasty, sharp smell.

It reacts easily with other substances to form harmful compounds, such as sulfuric aci sulfurous acid and sulfate particles. About of the sulfur dioxide in air comes from human sources. Another category of the primary air pollutants is toxic metals such as Cadmium, Lead and Copper, which are products of the Industrial processes.

The Chlorofluorocarbons (CFCs) are proved to be harmful to the ozone layer emitted from products currently banned from use. The pollutants that are emitted directly from a combustion process – or the products of combustion - are called “ primary pollutants. We just described these products earlier in the lesson, now we will look at their impact on the environment and human health. Pollution kills more people than malaria, AIDS and tuberculosis combined. Pollutants are classified as either primary or secondary pollutants.

Certain primary pollutants can react with other elements or compounds, creating new chemicals that are known as secondary pollutants. Start studying primary air pollutants. Learn vocabulary, terms, and more with flashcards, games, and other study tools.

Provide two examples of each type of pollutant. The phenomena of photochemical smog (seen in high density cities, see Figure 1) is a result of the interactions of primary pollutants with other molecules in the air such as molecular oxygen, water and hydrocarbons. These combine to form yellow clouds that. Mobile sources account for more than half of all the air pollution in the United States and the primary mobile source of air pollution is the automobile, according to the Environmental Protection Agency.

Stationary sources, like power plants, emit large amounts of pollution from a single location, these are also known as point sources of pollution. Radon is a radioactive gas that seeps from the ground in some areas, and fog and mist are both dense water vapor at ground level that obscures vision. The major historical air pollution episodes all occurred during stagnant inversions in regions that had significant sources of combustion-related air pollutants (see Chapter 1).