If we try to define Load Line in the simplest fashion, it will be as follows:

“Load line is a special marking positioned amidships which depicts the draft of the vessel and the maximum permitted limit in distinct types of waters to which the ship can be loaded.”

As a result of the numerous maritime accidents that have happened at sea due to the overloading of vessels, the significance of having a standard maximum limit for ships was identified long before. However, it took many years from then to have an International agreement for the universal application of Load lines.

It was in 1930, when the first International Load Line Convention took place, after which, it was periodically amended until the latest one that happened in 2003.

The fundamental purpose of a Load Line is to allow a maximum legal limit upto which a ship can be loaded by cargo. By prescribing such limits, the risk of having the vessel sailing with inadequate freeboard and buoyancy can be limited. A vessel should be having sufficient freeboard at all times, any exceptions made will result in insufficient stability and excessive stress on the ship’s hull. This is where load-lines play an important role, as it makes the task of detecting whether the vessel is overloaded and its freeboard tremendously easy and effortless.

However, since the buoyancy and immersion of the vessel largely depend on the type of water and its density, it is not practical to define a standard freeboard limit for the ship at all times. For this reason, the load line convention has put regulations that divide the world into different geographical zones each having a different prescribed load line.

For example, A vessel sailing in Winter on North Atlantic Ocean will have a greater freeboard than on a voyage in Tropical Zones and Freshwaters.