The Ship Security Alert System (SSAS) is part of the ISPS code and is a system that contributes to the International Maritime Organization's (IMO)'s efforts to strengthen maritime security and suppress acts of terrorism and piracy against shipping. The system is an IMO regulated system. In case of attempted piracy or terrorism, the ship's SSAS beacon can be activated, and appropriate law-enforcement or military forces can be dispatched. An SSAS beacon operates with similar principles to the aircraft transponder emergency code 7700.
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Ship Security Alert System Wikipedia(Text) CC BY-SA