Regular smoke alarms can only do this one thing
Defending against fire is a crucial consideration, and smoke detectors play an essential part in shielding your family. However, smoke detectors have various limitations. For example, they can only identify smoke, not extreme temperatures. If there is a fire in your residence, you would not be alerted until the smoke rises to the smoke detector. Although there are some other significant signals of fire -- including a marked rise in heat -- if you don’t have smoke, you won’t have a sounding of your smoke detector.
What’s more, smoke detectors only sound the alarm if they encounter an adequate amount of smoke. If a fire begins slowly, you might not be warned until the situation is out of hand. Some smoke detectors use more than one sensor, which means they will detect smoke from both roaring flames and a more gradual burn. Whenever they start beeping, it’s required of the resident to contact the fire department after they safely leave the premises.