How Often To Change Smoke Detectors Batteries. Estimated battery life in a smoke or carbon monoxide (co) detector can vary greatly based on battery type and brand, the environment where the alarm is installed and alarm usage. It might be easy enough to mark your calendar for one residential detector, but businesses and large corporate buildings hold more detectors than a house.
Since you cannot (and should not) replace the lithium battery, replace the entire smoke alarm according to the manufacturer's instructions. Batteries often contain toxic metals, sometimes mercury. They can be checked once a month with batteries replaced at least once or even twice a year, according to the u.s.
Plus, used batteries often aren’t 100 percent dead yet.
It is best to be proactive and change the batteries in your smoke alarms before that noise occurs. Since you cannot (and should not) replace the lithium battery, replace the entire smoke alarm according to the manufacturer's instructions. The batteries in those devices serve as a backup power source in case the power goes off. How often should you change the batteries in your smoke and co detectors?