| A | B |
|---|
| air pollution | the contamination of the atmosphere by the introduction of pollutants from human and natural sources |
| primary pollutant | a pollutant that is put directly into the atmosphere by human or natural activity |
| secondary pollutant | a pollutant that forms in the atmosphere by chemical reaction with primary air pollutants, natural components in the air, or both |
| smog | urban air pollution composed of a mixture of smoke and fog produced from industrial pollutants and burning fuels |
| temperature inversion | the atmospheric condition in which warm air traps cooler air near Earth's surface |
| sick-building syndrome | a set of symptoms, such as headache, fatigue, eye irritation, and dizziness, that may affect workers in modern, airtight office buildings; believed to be caused by indoor pollutants |
| asbestos | any of six silicate minerals that form bundles of minute fibers that are heat resistant, flexible and durable |
| decibel (dB) | the most common unit used to measure loudness |
| acid precipitation | precipitation, such as rain, sleet, or snow that contains a high concentration of acids, often because of the pollution of the atmosphere |
| pH | a value that is used to express the acidity or alkalinity (basicity) of a system; each whole number on the scale inidcates a tenfold change in acidity; a pH of 7 is neutral, a pH of less than 7 is acidic, and a pH of greater than 7 is basic |
| acid shock | the sudden runoff of large amounts of highly acidic water into lakes and streams when snow melts in the spring or when heavy rains follow a drought |
