All fire alarms are to be taken seriously.
The signal to evacuate a building for a fire, fire drill or emergency is a series of rings on the building's fire bells. Evacuation of the facility is mandatory until the signal to re-enter has been given by appropriate personnel, and the alarm bells have ceased ringing. If possible, close all windows before leaving the room. Everyone should take their belongings with them and leave the building by means of the closest safe stairway and exit in an orderly manner. If possible, close but do not lock the door if you are the last person to leave the room.