Sea fishing is subdivided into :
1. Offshore fishing: absence from port of 24 hours or less ;
2. Coastal sea fishing: absence from port of between 24 and 96 hours ;
3. Middle-water fishing: absence greater than 96 hours, when this does not meet the definition of deep-sea fishing ;
4. Deep-sea fishing :
a) Ships of more than 1,000 gross registered tons (GRT) ;
b) Ships of more than 150 tons that are habitually absent more than 20 days from their port of operations or victualling yard ;
c) Ships of more than 150 tons whose home port is more than 20 days away from their port of operations or victualling yard.
The port of registry corresponds to the port of administrative management of the ship