What is one of the key features of smoke detectors?

One of the key features of smoke detectors is their ability to detect the earliest possible stages of a fire. This early detection is crucial because it provides a critical window of opportunity to respond to potential fire hazards before they escalate into an emergency. Smoke detectors are designed to sense smoke particles in the air, which may indicate that a fire is beginning. The sooner a smoke detector identifies smoke, the quicker occupants can be alerted to evacuate and reduce the risk of injury or property damage.

The other choices do not accurately describe the primary function of smoke detectors. Some smoke detectors can indeed detect smoke from a wide range of materials, rather than being limited to specific types. They are designed to operate automatically, freeing occupants from the need to manually activate them in an emergency. Additionally, smoke detectors are suitable for both residential and commercial environments, making them versatile safety devices that should be utilized in various settings, not just homes.