You should test your smoke detector monthly, at the very least once every 6 months. Most detectors have a button you can push to test them. Change the batteries in your smoke detector at least once a year. A handy way to remember to change your batteries is to do it when you change your clocks for daylight savings time. Smoke detectors should be replaced at least every ten years. Never disable your smoke detector by removing the batteries. Remember, a smoke detector that isn’t working cannot save you.