What Causes Air Pollution 12-1

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Air

• 78% Nitrogen• 20 % Oxygen• Carbon

Dioxide, Argon and water vapor

Primary Pollutant

• Put directly into the air by human activity

• Example: Particulates from smoke

Secondary Pollutants

• Form when primary pollutants react with naturally occurring substances such as water vapor

• Example: Ground level ozone forms when Ultraviolet light causes emissions from cars to react with Oxygen from the atmosphere

Primary Pollutants

• Carbon Monoxide

• Incomplete burning of fossil fuels

• Lowers blood oxygen levels

Video

Nitrogen Oxides

• Combustion temperatures above 538 C.

• From fuels in autos and power plants

• Causes Lung disease and cancer

Sulfur Dioxide

• Comes from burning fossil fuels and Volcanoes

• Forms sulfuric acid and acid precipitation

• Harmful to plant and animal life

Volatile Organic Compounds (VOCs)

• Vaporize readily

• Vehicles a major source

• Smog formation, cancer, harmful to plants

Particulate Matter (PM)

• Many sources – in valley agriculture and autos

• Respiratory problems, cancer. Corrosion of metal and cement.

Motor Vehicle Emissions

• Almost one third of our air pollution comes from vehicle emissions

• Clean Air Act 1970 and 1990 gives Us ability to regulate

• Lead in gasoline gone

California

• Wants standards stricter than US but can not

• ZEV – Zero Emission Vehicle program

• Electric cars and fuel cell cars

Industrial Air Pollution

• Burning of Fossil fuels in many industries

• Also, some give off VOC’s

• Locally PM are monitored at farms and gravel mines

Air scrubber for VOC

Smog

• From chemical reactions that involve sunlight, air, auto exhaust and ozone

Temperature Inversion

• High Pressure can trap air under it forming an inversion