Smog: Frequently Asked Questions

Learn more about smog and ground-level ozone

Smog, also known as ground-level ozone, poses serious risks to public health and the environment. In this series of frequently asked questions, you can learn more about smog, its causes and effects, and whether smog is threatening your health.

• What is Smog?
  Just about everybody recognizes smog when they see it, but how many really know what they’re looking at?

• How Did Smog Get Its Name?
  Who coined the term “smog” and how long has it been around?

• What Causes Smog?
  What mix of chemicals and conditions must be present to produce what we call smog?

• Where Does Smog Occur?
  Why is smog more prevalent in some places than in others?

• What are the Effects of Smog?
  Smog is a serious health issue in many locations, but did you know that it can also cause property damage and harm the environment?

• Who is Most at Risk from Smog?
  Four types of people are particularly sensitive to smog and most at risk to the health problems it can cause. Are you one of them?

• How Can You Recognize or Detect Smog Where You Live?
  To protect yourself from the adverse effects of smog, you first have to know when you’re at risk. Find out how you can get that information.