Crews responded to a fire on the roof of Jefferson Hospital on Tuesday.
The small fire that broke out shortly before 11:30 a.m. caused smoke to get into the hospital's upper floors through the air handling system, a spokesperson for Allegheny Health Network said in a statement.
Some floors were impacted by smoke, but patient care areas weren't significantly affected and the building wasn't evacuated, AHN said. The impacted floors were ventilated to clear any remaining smoke. "From my understanding, there was some welding going on that caught some insulation on fire and that spread and that caused some smoke to go throughout the building. Most of what we were dealing with today was ... smoke fumes," said AHN public relations director Bill Toland.