APES Unit 7: Air Pollution

Air Pollution

the contamination of the atmosphere by the introduction of pollutants from human and natural sources

SO2

sulfur dioxide pollutant that can combine with water to make sulfuric acid (H2SO4) rain

NOx

Nitrogen based pollution typically from cars that can combine with water to form nitric acid (HNO3) rain

Peroxyacetyl Nitrate

A pollutant formed from photochemical reactions involving nitric oxide (NO) and volatile organic compounds (VOCs). PAN produces no known human health effect, but is particularly damaging to plants.

Point Source Pollution

Objects that are a source of pollution

Primary point source pollution

Specific large location that generates pollution

Secondary point source pollution

Many small sources of pollution that are widespread and nonspecific

Brown air smog

caused by NO2, source of the brown-ish haze that hangs over many cities during the afternoons of sunny days. Photochemical smog is sometimes called brown-air smog.

Volatile Organic Compounds (VOCs)

organic compounds that become vapors at typical atmospheric temperatures. Prevents ground level ozone breakdown

Industrial Smog (gray smog)

smog resulting from emissions from industry and other sources of gases produced by the burning of fossil fuels.

Thermal Inversion

The temperature inversion in which warm air traps cold air and pollutants near the earth.

Particulate Matter (PM)

Solid or liquid particles suspended in air; also known as particles and particulates.

Aerosols

tiny solid particles or liquid droplets that remain suspended in the atmosphere for a long time

Indoor Pollutants

chemical, biological and physical contamination of indoor air

Asbestos

A long, thin, fibrous silicate mineral with insulating properties, which can cause cancer when inhaled.

Radon-222

Naturally occurring colorless and odorless radioactive gas found in some types of soil and rock

Pollen

Allergen created by plant reproduction

Mold

Potentially dangerous indoor pollutant from fungal growth

Animal dander

flakes of dead skin from an animal

Dust

Collection of particles made of skin cells, fibers from fabrics, and dirt

Sick Building Syndrome

a buildup of toxic pollutants in an airtight space causing sickness of people who live and work in these buildings

Noise Pollution

Type of pollution characterized by unwanted or potentially damaging sound.

vapor recovery nozzle

an air pollution control device on a gasoline pump that prevents fumes from escaping into the atmosphere when fueling a motor vehicle

Catalytic Converter

a device that reduces carbon monoxide emissions from vehicles.

Scrubbers

devices containing alkaline substances that precipitate out much of the sulfur dioxide from industrial plants.

Wet Scrubbers

remove particulates by passing the pollution gases through water

Dry Scrubbers

use dry reagents to neutralize or convert the exhaust gases. Converted materials fall out of the gas stream and are then collected. The cleaned gases are then released.

Electrostatic Precipitators

A device used for removing particulates from smokestack emissions. The charged particles are attracted to an oppositely charged metal plate, where they are precipitated out of the air.

National Ambient Air Quality Standards (NAAQS)

standard followed by the EPA to specify concentration limits for each air pollutant

Air Quality Index (AQI)

a measure of ozone, sulfur dioxide, carbon monoxide, and fine particles close to the ground to determine safety of the air breathed in

Smog

haze caused by the interaction of ultraviolet solar radiation with chemical fumes from automobile exhausts and other pollution sources