Citizen devices track Chicago's pollution hot spots
CHICAGO - With a variety of palm-size devices strapped across her chest and connected wirelessly to her smartphone, Gail Merritt discovered the air in Chicago's South Loop might be a lot dirtier than expected.
Merritt and her group of volunteer pollution hunters had assumed the low-cost sensors they carried during daily walks would confirm their fast-growing neighborhood had relatively decent air quality, at least when compared with the gritty industrial corridors in other parts of Chicago.
Color-coded graphs
