As soon as the power went out the first time and the ventilation system shut down, Piero Chessa and I immediately left the clean room to avoid causing any problems. When the power came back on, the ventilation system restarted, and we were trying to figure out what to do (again from outside the clean rooms) when the power went out a second time. After about 5 minutes, it came back on, but this time the ventilation system didn't restart. So we left the central building and went to the control room, where they reported no problems with the central building's ventilation system.
At this point, Davide Soldani was called, and we went with him to the central building where he had to manually restart the ventilation system. At this point, we decided to suspend all operations until the next morning to allow the clean rooms time to return to a stable state.