How Can You Recognize or Detect Smog Where You Live?

Question: How Can You Recognize or Detect Smog Where You Live?

Answer: Generally speaking, you will know smog when you see it. Smog is a visible form of air pollution that often appears as a thick haze. Look toward the horizon during daylight hours, and you can see how much smog is in the air.

In addition, most cities now measure the concentration of pollutants in the air and provide public reports—often published in newspapers and broadcast on local radio and television stations—when smog reaches potentially unsafe levels.

The U.S. Environmental Protection Agency (EPA) has developed the Air Quality Index (AQI) (formerly known as the Pollutant Standards Index) for reporting concentrations of ground-level ozone and other common air pollutants.

Air quality is measured by a nationwide monitoring system that records concentrations of ground-level ozone and several other air pollutants at more than a thousand locations across the United States. The EPA then interprets that data according to the standard AQI index, which ranges from zero to 500. The higher the AQI value for a specific pollutant, the greater the danger to public health and the environment.