CHICAGO - Five people were hospitalized for carbon monoxide exposure in West Humboldt Park Wednesday morning.
The Chicago Fire Department responded to 1638 North Keystone Avenue for a level one hazmat situation.
A man showed up to work and had symptoms of CO poisoning. His boss took him home where they found other family members unresponsive, according to CFD.
Several people refused medical care after carbon monoxide levels peaked over 350 ppm.
Fire officials warn residents should have working CO detectors.