Stability and Freeboard
For a vessel to be considered seaworthy, it must have sufficient stability properties and be sufficiently water- and weathertight to be able to carry passengers, cargo or to perform other work under all sea conditions it can be expected to be exposed to. All passenger ships, recreational craft with tonnage above 100 and other vessels with tonnage above 20 must have their stability properties documented so that the master can ensure that the vessel is loaded correctly and can be sailed in a seaworthy manner. Some categories must also demonstrate adequate stability after damage on the hull.
There are a number of different regulations that contain rules for stability, but the Swedish Maritime Administration’s decree with regulations on ship stability and freeboard (SJÖFS 2006:1) is at this time the main one. This regulation also specifies how stability properties shall be documented and proven, as well as freeboard (load lines) regulations for most vessels.
The standards in our regulations for vessels in international traffic are based on international agreements. The International Convention for Safety of Life at Sea (SOLAS) applies to construction and stability and load line standards are set by the International Convention on Load Lines (ICLL).