If someone is on fire, try smothering the fire with a coat or have him or her drop and roll on the ground. Small electrical fires often extinguish themselves when the device is unplugged. Treat all alarms as real fires until you are told otherwise. Do not reenter until someone in authority has told you it is all right to do so. The alarm being turned off is not necessarily an indication that it is safe to reenter the building.
Most power outages are brief.
Contact the facilities director or someone in charge. In off-hours, if you are unable to contact anyone, close the facilities after 30 minutes if power is not restored. Stay with the person and administer whatever assistance you feel comfortable giving. Then go to a safe part of the building. If you are already at work and severe weather starts to develop, contact your supervisor.