The city is racing to put up 277 sensors. Once installed, Chicago will have the most high-quality air monitors in the country, a model that rivals only London, which has more than 400.| WBEZ
"The air quality is officially dangerous in Chicago," says Brian Urbaszewski, director of environmental health programs at the Respiratory Health Association. "It's going to send people to the emergency room. Some people may die because of what they're breathing."| WBEZ