Wildfire smoke is like smoking 'half a pack a day.' Here's how to protect yourself

People wear masks in Chicago on Thursday to protect themselves from smoke from Canadian wildfires. City officials are encouraging people to remain inside as data shows Chicago having some of the worst air quality of any large city in the world.

As Canadian wildfires spread smoke across the U.S. the air pollution is dangerous to health. But there are ways to protect yourself. Here's what to know**.**

(Image credit: Scott Olson)