Traditional smoke alarms can only do this one thing
Protecting your home from fire is a chief concern for homeowners, and smoke detectors play a vital role in shielding your family. Even so, smoke detectors have some drawbacks. For instance, they will only identify smoke, not heat. If there is a fire in your home, you might not be alerted until the smoke reaches the smoke detector. Even though there are additional telltale signs of fire -- such as a sudden heat increase -- if there’s a lack of smoke, there is no warning from your smoke detector.
Additionally, smoke detectors only sound the alarm when they detect ample smoke. In the event a fire begins slowly, you may not be warned until the situation is out of hand. Various smoke detectors use dual-sensor technology, meaning they will recognize smoke from both a raging fire and something less intense. Whenever they start beeping, it's up to the homeowner to notify first responders after exiting the residence.