Official numbers are
ship identifier numbers assigned to merchant ships by their
country of registration. Each country developed its own official numbering system, some on a national and some on a port-by-port basis, and the formats have sometimes changed over time. As an internationally recognized ship identifier, national official numbers have largely been superseded by the
IMO number
The IMO number of the International Maritime Organization is a generic term with two distinct applications:
* the IMO ship identification number is a unique ship identifier; or,
* the IMO company and registered owner identification number is u ...
, though flag states still use national systems, which also cover those vessels not subject to the IMO regulations.
British official number
Beginning in 1855, with the implementation of the
Merchant Shipping Act 1854, all British seagoing vessels were assigned an official number to give each ship a unique identity, even after being renamed or changing the port of registry.
U.S. official number
After the passage of legislation in the
United States Congress
The United States Congress is the legislature, legislative branch of the federal government of the United States. It is a Bicameralism, bicameral legislature, including a Lower house, lower body, the United States House of Representatives, ...
in 1866, all American ships were required to carve the official number on the main beam; the system was controlled by the Bureau of Statistics.
See also
*
IMO number
The IMO number of the International Maritime Organization is a generic term with two distinct applications:
* the IMO ship identification number is a unique ship identifier; or,
* the IMO company and registered owner identification number is u ...
*
Hull number
A hull number is a serial identification number given to a boat or ship. For the military, a lower number implies an older vessel. For civilian use, the Hull Identification Number (HIN) is used to trace the boat's history. The precise usage varie ...
References
External links
* {{cite book , title=Annual List of Merchant Vessels of the United States , publisher=U.S. Government Printing Office , issue=v. 35, pt. 1903 , year=1903 , url=https://archive.org/details/annuallistmerch00navigoog , via=Internet Archive
Ship identification numbers