Change Your Clock, Change Your Battery
NFPA provides the following guidelines around smoke alarms:
Test smoke alarms at least once a month using the test button.
Make sure everyone in the home understands the sound of the smoke alarm and knows how to respond.
Replace all smoke alarms when they are 10 years old.
Replace the smoke alarm immediately if it doesn’t respond properly when tested.
Smoke alarms with nonreplaceable (long-life) batteries are designed to remain effective for up to 10 years. If the alarm chirps, a warning that the battery is low, replace the entire smoke alarm right away.
For smoke alarms with any other type of battery, replace batteries at least once a year. If the alarm chirps, replace only the battery.