Garmin GPSMAP 190-01230-10 Owner's Manual page 61

aiS alarm—create a safe zone around your boat for collision
avoidance. The zone can be customized.
To customize safe-zone settings:
From the Home screen, select
Alarm.
• Range—change the measured radius of the safe-zone ring to
a specified distance from 500 ft. to 2.0 nm (or from 150 m to
3.0 km, or from 500 ft. to 2.0 mi).
• Time to (Safe Zone)—sounds an alarm if AIS or MARPA
determines that a target will intersect the safe zone within the
defined time interval (from 1 to 24 minutes).
• AIS Alarm—when On is selected, a message is displayed
("AIS: Dangerous Target") when a vessel enters the safe
zone. When Off is selected, the message will not be
displayed.
GPSMAP 400/500 Series Owner's Manual
Configure > Other Vessels > AIS
Configuring the Chartplotter
55