Smoke entering the emergency room at UC Irvine Medical Center prompted officials to evacuate the building early Tuesday morning.
The incident occurred just after 2 a.m. when smoke began entering the room from the basement below, UCI Health spokesperson John Murray said.
Staff members immediately began removing about 75 patients from the emergency department and took them to other buildings, Murray said.
“The staff responded appropriately, as they are trained to do,” he said.
Ambulances and paramedics had to be diverted to other hospitals during the closure.
The emergency room will take several hours to air out, Murray said. “Just making sure that the smell and other smoke residue is gone,” he said.
A Medical Center spokesperson confirmed the emergency room would reopen at 10 a.m.
The smoke was coming from a generator that caught fire in the basement, an Orange County Fire Authority captain at the scene said.
A facility crew responded to the building and determined there was no structural damage, Murray said.