This is the most important 10-minute job on the list. Do it once a month.
Difficulty: Easy. Plan on 10 min.
Safety: Use a stable step ladder, not a chair.
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Use a stable step ladder, not a chair.
Press and hold the test button on each alarm until it sounds.
Replace batteries in any alarm that's weak or chirping, if the battery is replaceable.
Check the date on the back of each alarm. Replace smoke alarms 10 years after the manufacture date, and carbon monoxide alarms when the manufacturer says to.
Make sure there's an alarm on every level and outside sleeping areas.
Nice work. A new fix shows up every day, and the Fix Ladder has step-by-step guides for common home repairs.