99% Invisible: The Plimsoll Line


If you look at the outer hull of commercial ships, you might find a painted circle bisected with a long horizontal line. This marking is called the load line, or as I prefer, the Plimsoll line. This simple graphic design has saved thousands of lives. The Plimsoll line shows the maximum loading point of the ship and lets a third party know, plainly and clearly, when a vessel is overloaded and at risk of sinking in rough seas. If you see that horizontal line above the water, you’re good, if you don’t, you could be sunk.