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 non-replaceable (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.
For more on smoke alarm safety, check out NFPA’s smoke alarm safety tip sheet, and new 9-volt battery tip sheet which explains the importance of storing and disposing of batteries with care to avoid a fire hazard.