Replace smoke detector batteries

Why It Matters

Dead batteries are the most common reason smoke detectors fail during fires.

Tools

• Step ladder

Materials

• Replacement batteries (check the compartment label for size, typically 9V or AA)

How to Do It

1. Gather replacement batteries before you start, checking each detector's battery compartment or manual for the correct size.
2. Remove the detector from its mounting bracket by twisting or sliding it off, depending on the model.
3. Open the battery compartment, remove the old battery, and insert the replacement.
4. For hardwired detectors, open the backup battery compartment separately and replace that battery as well.
5. Press the test button and confirm the alarm sounds before reattaching the unit to its bracket.
6. Repeat for every smoke detector in the home.

Related Tasks

• Press test button on smoke detectors Monthly
• Replace smoke detector units Every 10 years
• Radon test Every 2 years