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SHENANGO TOWNSHIP (KDKA) — At approximately 6:32 p.m., a local ambulance service responded to a call from a husband and wife complaining of carbon monoxide type symptoms at the Shenango Tree Tops Assisted Living Facility on Frew Mill Road in Shenango Township, and the residents were evacuated.

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When the ambulance service arrived, their CO detectors alerted them to an elevated CO level. They were taken to the hospital for evaluation.

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Firefighters searched the three story building for the source of the smell and awaited the arrival of the gas company to determine if it would be safe for residents to return to their apartments. Their search found nothing unusual, according to David Rishel, Shenango Township Fire Chief.

The gas company found a problem with the clothes dryers and red-tagged them, putting them out of service.

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The residents were allowed to return to their rooms by 9:00 p.m.