From ChicagoTribune.com:
Chicago, IL – High carbon monoxide levels, apparently the result of a truck left idling in a ground-level parking area, caused firefighters to clear a Dunning neighborhood apartment building shortly before 12:30 p.m. this afternoon.
Firefighters were called to the building in the 4100 block of North Narragansett Avenue; commanders were called at Level II Hazardous Materials response a few minutes later.
Crews cleared all residents from the building, which has about 24 units, and found carbon monoxide levels of about 400 parts per million, said Chicago (IL) Fire Department spokesman Chief Joe Roccasalva.
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