Regular smoke alarms can only do this one thing
Fire safety is a chief concern for homeowners, and smoke detectors take on a critical part in shielding your family. Even so, smoke detectors have some shortcomings. To illustrate, they are only able to react to smoke, not heat. In the event there is an emergency in your home, you might not be warned before the smoke reaches the smoke detector. Even though there are additional unmistakable signs of fire -- like a marked rise in heat -- if you don’t have smoke, you won’t have a triggered smoke detector.
What’s more, smoke detectors only beep if they detect an adequate amount of smoke. In the event a fire starts small, you might not be cautioned until it's too late. Some smoke detectors employ more than one sensor, meaning they will recognize smoke from both a blazing inferno and something less intense. If they do go off, it falls to the resident to call emergency services after exiting the residence.