By Shelby Cassesse

OAKMONT, Pa. (KDKA) – Seventy-six residents at Oakmont Nursing and Rehab Center were evacuated Thursday afternoon.

(Photo Credit: KDKA)

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Allegheny County Emergency Services Chief Matt Brown says maintenance employees poured a drain cleaner into a clogged slop sink, which had a reaction and started fuming.

“The cause of the chemical odor was a reaction caused by the use of a drain cleaner and other chemicals to unclog a sink,” Allegheny County HMRT 420 said on Facebook.

The facility chose to evacuate its residents, with Emergency Services implementing its mass casualty incident protocol to help evacuate 76 residents.

Port Authority brought in two buses and operators for temporary shelter until the building is ventilated by HAZMAT and firefighters.

“MCI plan was put into effect bringing ambulances in from all over the county just to make sure we can properly care for the patients. Port Authority busses were brought in,” Asst. Chief Steve Imbarlina of Allegheny County Emergency Services.

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WATCH: KDKA’s Shelby Cassesse Reports Live From Oakmont

There are no unusual meter readings, Brown says, and the facility is now being cleaned.

“They start to make sure that it is safe to reoccupy and that the air quality is just as good as the air out here,” Imbarlina said.

Officials say no one was taken to the hospital and residents were allowed back in on Thursday night.

“As a general reminder, drain cleaners are harsh chemicals and should be used cautiously under close supervision,” Allegheny County HMRT 420 said on Facebook.

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