Fire protection specialists recommend that every home be equipped with smoke detectors. It is important that the detector be tested and maintained on a regular basis to ensure it functions if needed. A smoke detector that is disconnected due to nuisance alarms or low batteries provides no protection in the event of a fire. Current building codes require smoke detectors be hardwired into the electric system with a battery back-up. In the event of a power outage, the alarm would still function, using the battery for power.
The United States Fire Administration (USFA) recommends that smoke alarms be tested monthly.
Batteries should be replaced yearly. The entire unit should be replaced every 8 to 10 years. Even a hardwired smoke detector will beep or chirp to indicate a low or dead battery so you know it is time to replace it.
Cooking malfunctions, extra hot showers, fireplaces with bad draft can all cause an alarm to go off. Do not disconnect the alarm, consider it a test and be thankful it works. Press the hush button, reset the alarm and use a towel to clear the smoke or steam away from the detector.
The USFA recommends installing smoke detectors in multiple locations. Every level of the home should have one, including the basement. Every bedroom should have one inside and outside the sleeping area.
The USFA says smoke detectors should be networked together. When one goes off, all the alarms go off. Smoke alarms should be wired into the electrical system and only depend on a battery when the power is out. Batteries in hardwired units follow the same protocol as battery-only units: replace a battery once a year.