Dust or dirt that accumulates inside the smoke detector, or tiny insects that enter the device, can also trigger an alarm. ... It's important not to damage the sensors during cleaning.

If a sound accompanies your smoke detector's flashing red light, however, it may mean that immediate action needs to be taken. The reasons for this can vary depending on your brand of smoke detector.

Smoke detector false alerts happen, although our top picks like Kidde use sensors designed to cut down on them. If you hear a smoke alarm, check for the source of the smoke before calling 911.

A smoke detector should be replaced every 10 years, according to the U.S. Fire Administration. That's because the sensors inside the alarm deteriorate, and lose their effectiveness over time.

Shopping for a smoke and carbon monoxide detector? Read about features, types, and other must-know details in our buying guide to make an informed choice.