PLIMSOLL MARKINGS

PLIMSOLL MARK is a load line marking on the side of a ships hull. It shows how much cargo the ship can carry safely under different conditions. The position of the marking depends on the type and size of vessel. The name came from the load-line markings on British merchant ships owned by Samuel Plimsoll. It was through Plimsoll’s effort that an act of Parliament to prevent overloading was passed. A ship loaded "down to the Plimsoll Mark" carries capacity cargo. Any more cargo would lessen its chance of a safe voyage.

Load lines on American ships have been established by the American Bureau of Shipping as provided under the Load Line Act of 1929. These rules apply to deep sea vessels of 150 gross tons or more.

The distance between the Plimsoll Mark and the deck is the ship’s "freeboard". Special markings were establihed in 1935 for Great Lakes and Atlantic and Pacific coast voyages.

PLIMSOLL MARK GREAT LAKES

The markings shown are for the starboard side; on the port side the markings are similar and forward of the diamond.

The letters AB signify American Bureau of Shipping

MS.........................Midsummer Load Line
S.........................Summer Load Line
I.........................Load Line in Intermediate Seasons
W.........................Winter Load Line
SW.........................Salt Water
FW.........................Fresh Water

Note: The salt water marks are assigned only to vessels intending to load in salt water in the St. Lawrence River.

 

 

 

FOREIGN OR COASTWISE LOAD LINE MARK

The markings shown are for the starboard side; on the port side the markings are similar, and forward of the disc.

The letters AB signify the American Bureau of Shipping.

TF.........................Tropical Fresh Water
F.........................Fresh Water
T.........................Load line in Tropical Zones
S.........................Summer
W.........................Winter
WNA.........................Winter North Atlantic