Battery or Hardwired Smoke Alarms?

The U.S. Fire Administration lists disposable 9-volt and nonreplaceable 10-year lithium-ion batteries for battery-powered alarms. Hardwired alarms use house power, usually with a backup battery.

Follow manufacturer instructions. Its general guidance: test monthly; replace 9-volt batteries and hardwired backups at least yearly; replace 9-volt and hardwired alarms every 10 years. Replace 10-year lithium alarms per manufacturer instructions.

Ask the local fire marshal which alarm type is needed; only qualified electricians should install hardwired alarms. USFA guidance

Confirm the exact model, wiring/interconnection and local requirement before choosing. This general guide establishes no fit for your home.