Lloyd’s Register Classification Symbols

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Lloyd’s Register Classification Symbols[edit]

A cargo shipper and the underwriter requested to insure a maritime risk require some assurance that any particular vessel is structurally fit to under- take a proposed voyage. To enable the shipper and underwriter to dis- tinguish the good risk from the bad a system of classification has been formulated over a period of some two hundred years. During this period reliable organizations have been created for the initial and continuing inspection of ships so that classification may be assessed and maintained. The principal maritime nations have the following classification societies:

  • Great Britain—Lloyd’s Register of Shipping
  • France—Bureau Veritas
  • Germany—Germanischer Lloyd
  • Norway—Det Norske Veritas
  • Italy—Registro Italiano Navale
  • United States of America—American Bureau of Shipping
  • Russia—Russian Register of Shipping
  • Japan—Nippon Kaiji Kyokai

These classification societies publish rules and regulations which are prin- cipally concerned with the strength of the ship, the provision of adequate equipment, and the reliability of the machinery. Ships may be built in any country to a particular classification society’s rules, and they are not restricted to classification by the relevant society of the country where they are built. Classification is not compulsory but the shipowner with an unclassed ship will be required to satisfy governmental regulating bodies that it has sufficient structural strength for assignment of a load line and issue of a safety construction certificate. Only the requirements of Lloyd’s Register of Shipping which is the oldest of the classification societies are dealt with in detail. Founded in 1760 and reconstituted in 1834, Lloyd’s Register was amalgamated with the British Corporation, the only other British classification society in existence at that time, in 1949. Steel ships built in accordance with Lloyd’s Register rules or equivalent standards, are assigned a class in the Register Book, and continue to be classed so long as they are maintained in accordance with the Rules.

Lloyd’s Register Classification Symbols[edit]

All ships classed by Lloyd’s Register of Shipping are assigned one or more character symbols. The majority of ships are assigned the character 100A1.

The character figure 100 is assigned to all ships considered suitable for sea-going service. The character letter A is assigned to all ships which are built in accordance with or accepted into class as complying with the Society’s Rules and Regulations. The character figure 1 is assigned to ships carrying on board anchor and/or mooring equipment complying with the Society’s Rules and Regulations. Ships which the Society agree need not be fitted with anchor and mooring equipment may be assigned the character letter N in lieu of the character figure 1. The Maltese Cross mark is assigned to new ships constructed under the Society’s Special Survey, i.e. a surveyor has been in attendance during the construction period to inspect the materials and workmanship.

There may be appended to the character symbols, when considered neces- sary by the Society or requested by the owner, a number of class notations. These class notations may consist of one or a combination of the following. Type notation, cargo notation, special duties notation, special features notation, service restriction notation. Type notation indicates that the ship has been constructed in compliance with particular rules applying to that type of ship, e.g. 100A1 ‘Bulk Carrier’. Cargo notation indicates the ship has been designed to carry one or more specific cargoes, e.g. ‘Sulphuric acid’. This does not preclude it from carrying other cargoes for which it might be suitable. Special duties notation indicate the ship has been designed for special duties other than those implied by type or cargo notation, e.g. ‘research’. Special features notation indicates the ship incorporates special features which significantly affect the design, e.g. ‘movable decks’. Service restriction notation indicates the ship has been classed on the understand- ing it is operated only in a specified area and/or under specified conditions, e.g. ‘Great Lakes and St. Lawrence’.

The class notation ? LMC indicates that the machinery has been constructed, installed and tested under the Society’s Special Survey and in accordance with the Society’s Rules and Regulations. Various other notations relating to the main and auxiliary machinery may also be assigned.

Vessels with a refrigerated cargo installation constructed, installed and tested under the Society’s Special Survey and in accordance with its Rules and Regulations may be assigned the notation ? Lloyds RMC. A classed liquefied gas carrier or tanker in which the cargo reliquefaction or cargo refrigeration equipment is approved, installed and tested in accordance with the Society’s Rules and Regulations may be assigned the notation ? Lloyds RMC (LG).

Where additional strengthening is fitted for navigation in ice conditions an appropriate notation may be assigned. The notations fall into two groups: those where additional strengthening is added for first-year ice, i.e. service where waters ice up in winter only; and those where additional strengthening is added for multi-year ice, i.e. service in Arctic and Antarc- tic. It is the responsibility of the owner to determine which notation is most suitable for his requirements.

FIRST-YEAR ICE[edit]

Special features notations are:

Ice Class 1As unbroken level ice with thickness of 1 m.
Ice Class 1A unbroken level ice with thickness of 0.8 m.
Ice Class 1B unbroken level ice with thickness of 0.6 m.
Ice Class 1C unbroken level ice with thickness of 0.4 m.
Ice Class 1D same as 1C but only requirements for strengthening the for- ward region, the rudder and steering arrangements apply.

MULTI-YEAR ICE[edit]

The addition of the term ‘icebreaking’ to the ship type notation, e.g. ‘ice- breaking tanker’ plus the following special features notation:

Ice Class 1AC1 Arctic or Antarctic ice conditions equivalent to unbroken ice with a thickness of 1 m.
Ice Class AC1.5 Arctic or Antarctic ice conditions equivalent to unbroken ice with a thickness of 1.5 m.
Ice Class AC2 Arctic or Antarctic ice conditions equivalent to unbroken ice with a thickness of 2 m.
Ice Class AC3 Arctic or Antarctic ice conditions equivalent to unbroken ice with a thickness of 3 m.

Ships specially designed for icebreaking duties are assigned the ship type notation ‘icebreaker’ plus the appropriate special features notation for the degree of ice strengthening provided.