I was interested to read the correspondence on the above subject and think that some clarification is required. Both registration and tonnage are often misunderstood even, I am sorry to say, by some marine surveyors. Registration is a legal requirement for merchant ships over 15 tons gross. It does not apply to warships or vessels of ‘primitive build’. It is written, like tonnage, into International, European and British law and cannot be changed at the whim of an owner or marine surveyor. Tonnage has nothing whatever to do with the vessel’s mass, weight or displacement but both gross and nett figures are a measure of the vessel’s internal volume. Nor has it anything to do, these days, with how much cargo (grain, bananas, wine tuns) that a vessel can carry but everything to do with harbour and light dues and taxation. The use of the word tonnage is merely an historical hangover and has been dropped for some time.
A Guide to the Registration of Ships
There are three classifications of registration in British law known from the divisions of the relevant Act of Parliament (the 1894 Merchant Shipping Act and subsequent revisions) as Parts I, II, and III. Part I applies, in general to big ships but may be used for ships under 24 metres load line length, Part II applies to fishing vessels and Part III to small craft under the 24 m load line length divisor. The vessel has to be measured for tonnage by an MCA authorised marine surveyor and the vessel’s registered Official Number and Registered Tonnage has to be ‘carved into the main beam’. The latter point is often circumvented by the material from which the vessel is built and the required data may be Continue reading “Registration and Tonnage explained”
