A dry docking Survey is required in conjunction with the Special Survey to examine the external underwater part of the ship and related items.
Two Bottom surveys are required to be carried out during the five year period of validity of SOLAS Cargo Ship Safety Construction (SC) Certificate, and the maximum interval between any two successive Bottom Survey is not to exceed three years.
From 1 July 2002, for bulk carriers of 15 years of age and over, inspection of the outside of the ship’s bottom is to be carried out with the ship in dry dock. For bulk carriers less than 15 years of age, alternative inspections of the ship’s bottom not conducted in conjunction with the Special Survey may be carried out with the ship afloat. Inspection of the ship afloat is only to be carried out when the conditions are satisfactorily and the proper equipment and suitably qualified staff are available.
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The Special (or Renewal) Surveys of the hull structure are carried out at five-year intervals for the purpose of establishing the condition of the structure to confirm that the structural integrity is satisfactory in accordance with the Classification Requirements, and will remain fit for its intended purpose for another five-year period, subject to proper maintenance and operation of the ship and to periodical surveys carried out at the due dates.
The Special Survey concentrates on close-up examination in association with thickness determination and is aimed at detecting fractures, buckling, substantial corrosion and other types of structural deterioration.
Thickness measurements are to be carried out upon agreement with the Classification Society concerned in conjunction with the Special Survey.
The Special Survey may be commenced at the 4th Annual Survey and be progressed with a view to completion by the 5th anniversary date.
Deteriorated protective coating in salt water ballast spaces and structural areas showing substantial corrosion and/or considered by the surveyor to be prone to rapid wastage will be recorded for particular attention during the following survey cycle, if not repaired at the survey.