What is the function of an automatic alarm system in a fire situation?

The function of an automatic alarm system in a fire situation is primarily to detect fire and alert occupants. These systems are designed to identify the presence of smoke, heat, or flames, often through various sensors and detectors. Once a fire is detected, the system activates alarms to warn building occupants, giving them critical information and time to evacuate safely. The effectiveness of this function is vital in minimizing the risk to life and property during fire incidents.

The other options, while related to fire safety, serve different roles. Providing emergency lighting helps ensure visibility during an evacuation but does not actively detect fire or notify occupants. Initiating evacuation procedures is a crucial action to take once an alarm has been sounded, but it is not the function of the alarm system itself. Controlling building access can be important for safety but does not relate directly to the detection of fire. Therefore, understanding the primary role of an automatic alarm system sheds light on its importance in fire prevention and safety operations.