These are non-governmental organisations that draw up and maintain the standards for the construction and continued seaworthiness of vessels, including offshore structures such as oil rigs and platforms. Some of the main classification societies are as follows (The abbreviation that appears as part of a ship’s loadline and the country in which the classification society has its headquarters are given in brackets :

Lloyd’s Register (LR – Britain); American Bureau of Shipping (AB – USA); Det Norske Veritas/Germanischer Lloyd (DNV-GL – Norway/Germany); Bureau Veritas (BV – France),

The role of classification societies focuses on ship construction, seaworthiness, marine accidents, and special surveys, and in summary, the following are the main activities of the classification society:

  • Approve ships’ plans and specifications before the vessels are built.
  • Monitor the construction programme in the shipyard where the ship is being built. (This is to ensure that the ship is being built according to the approved specifications.)
  • Conduct various trials on new ships – stability tests, sea trials, lifting trials of ships’ cranes, etc – prior to the owner taking delivery.
  • Conduct periodic surveys of ships to check their general seaworthiness and that maintenance is being carried out according to the minimum requirements of the classification society
  • Approve any plans to modify the ship in any way (e.g. a containership owner wishes to modify the ship so that she can carry more containers)
  • After an accident, check the seaworthiness of any ship registered with that classification society.
  • Undertake special surveys of ships every five years.

The periodic surveys and surveys following an accident are done by marine surveyors who have been accredited by the classification society. They are usually people with sea-going experience and are either qualified as chief engineers or master mariners. If the classification society finds that the ship is not being maintained according to the required standards, it will “withdraw class” which will lead to the insurers withdrawing insurance and ultimately, the flag state control will also detain the ship.