Ship tonnage: Its use and  an aproximate calculation method.

DEFINITIONS


The concept of ship tonnage is related to her size or volume, but it is not a physical particular than can be expressed in any measurement unit, but it is the result of some calculations performed with the ship's dimensions by applying a set of agreed rules.


Until recent times the words ship tonnage were suggesting that they referred to a weight when actually it is a volumetric concept. Ship tonnage nowadays is adimensional.


There are three tonnage classes: Gross, Net and Compensated gross