The Cortex smartAIS alarms can be silenced from any view using the Alarm Control, accessible from the top right hand bell icon.
The bell will turn red when there is an active alarm. Each alarm type can be controlled individually. Using the Silence All Alarms will silence all alarms globally for 5 minutes while you get on and get control of the situation. If there is an active alarm, tapping on the alarm type will take you directly to the situational view.
Note, you may have an alarm that is active but currently silenced. For example, you may silence the Collision alerts, but keep your Collision Alarm Settings configured to continue to display high priority targets in your plotter view.