If it is beeping due to a low battery, replace the battery
If it is a hardwired alarm, turn off power at the circuit breaker first
Press and hold the hush or silence button if the alarm is false
Remove the detector from its mounting bracket if you need to replace it
Disconnect the wiring harness only after power is off
Remove the battery from the unit if it is battery-powered
Reinstall or replace the detector as soon as possible
If there is any sign of smoke or fire, do not turn it off
Call emergency services if there is a real fire or you are unsure