Investigators say a faulty damper that kept carbon monoxide from being vented through a chimney was responsible for an apartment building being evacuated in Pittsburgh.
The incident occurred Sunday morning at the King Edward Apartments, which house about 180 people in the city's Oakland neighborhood.
One tenant's carbon monoxide detector alerted emergency crews who evacuated the building then used fans to force fresh air into the 10-story building. Residents were also tested for levels of the poisonous gas in their blood as a precaution.
One person had to be treated at a hospital, but otherwise nobody was reported hurt.
The residents were allowed to return home shortly before 3 p.m. Sunday.
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