| A | B |
|---|
| air pollution | harmful substances built in the air at unhealthy levels |
| primary pollutant | a pollutant that is put directly in the air by human activity |
| secondary pollutant | when 2 primary pollutants come together or with naturally occurring substances |
| smog | pollution that hangs over urban areas and reduces visibility |
| temperature inversion | the air above is warmer than the air bellow |
| sick-building syndrome | buildings that have very poor air quality |
| asbestos | minerals that form in long, thin fibers and resist to heat |
| decibel | units that measure the intensity of sound |
| acid precipitation | precipitation that contains a high concentration of acids |
| pH | a measure of how acidic or basic a substance is |
| acid shock | a sudden influx of acidic water that causes a rapid change in the water's pH |
