Tsunami sirens will be tested at north and west Auckland beaches in April.
The sirens will sound three times, using three sets of tones, which each signal a different message: alert, evacuate or all clear.
Each tone will sound for one minute, with 15 seconds in between.
In a real emergency the sirens sound from between five and 15 minutes.
Auckland head of emergency management operations Angus McKay said the sirens were tested every six months.
