What happens when smoke is detected by a smoke detector?

When smoke is detected by a smoke detector, the primary function is to emit a loud alarm. This loud alarm is designed to alert the occupants of the building to the presence of smoke, which is often an indication of fire. The primary purpose of the smoke detector is to provide early warning to help occupants evacuate the premises safely and to encourage them to take immediate action, such as calling the fire department.

The other potential responses do not accurately represent the functionality of standard smoke detectors. For example, smoke detectors are not responsible for notifying the fire department directly, as this is typically a function of a monitored fire alarm system rather than a standalone smoke detector. Additionally, smoke detectors do not have the capability to extinguish fires; that responsibility lies with fire suppression systems or extinguishers. Finally, alerting local police is not a function associated with smoke detectors; their primary role is focused on fire detection.