What is a common sign that a smoke detector needs battery replacement?

A smoke detector emitting a chirping sound is a well-known indicator that it needs a battery replacement. This sound is an alert designed to notify users that the power source is running low. The chirping generally occurs at regular intervals and can serve as a critical reminder to maintain the device, ensuring it remains effective in detecting smoke and alerting occupants in case of a fire.

The other signs mentioned, such as a detector glowing constantly or changing color, do not typically indicate a need for battery replacement. A constant glow often signifies that the smoke detector is functioning normally, while a change in color may suggest issues unrelated to battery life, such as the need for cleaning or a malfunction. A smoke detector that stops detecting smoke is a serious concern, but it may not be linked directly to battery status—it could indicate a malfunction or the need for replacement rather than simply a battery issue.