The Australian Maritime Safety Authority (AMSA) issued a Notice reminding the maritime community of the correct use of marine hydrometers. There are two types of marine hydrometers. Load line hydrometers are used to determine displacement of the ship at a given waterline and enable compliance with the Load Line Convention. Draught survey hydrometers are used to determine the apparent weight of the ship and from this the commercially accepted weight or apparent density of the cargo on board. Draught survey hydrometers should not
Source: HK Law