On the Live View screen, Siren controls appear when you tap the More  button in the lower right of your screen. When you tap the Siren On button, a Turn On Siren screen displays, which explains the loudness and 30 second duration of the siren sound.

At this point, tap the Turn on Siren button and the siren will run for 30 seconds. Tapping the Siren Off button manually stops the siren.

Note: The Siren volume and duration time of 30 seconds is not adjustable.

The following is true while the siren is on:

• Two-Way Audio is disabled on the camera.
• If the Live View has ended, the siren will stop. 
• The Reset button on the camera is disabled.