What is the primary function of a smoke detector?

The primary function of a smoke detector is to notify occupants of smoke presence. These devices are designed to detect the initial signs of fire, specifically the smoke that is generated in the early stages of combustion. When smoke is detected, the smoke detector emits a loud alarm, which serves to alert individuals in the vicinity, allowing them time to respond appropriately, whether that be evacuating the premises or taking other safety measures.

This function is critical for ensuring the safety of occupants, as early detection of smoke can significantly reduce the chances of injury or loss of life due to fire. Other options, such as alerting the fire department directly, are not the primary role of smoke detectors; instead, they rely on individuals recognizing the alarm and calling for help if needed. Monitoring air quality is another function that certain advanced systems may have, but it is not the main task of standard smoke detectors. Similarly, extinguishing fires upon detection is outside the scope of what smoke detectors do, as their role is limited to detection and alarm.