On February 3, 2000, International Maritime Organization (IMO) adopted a harmonised survey system for ships, in order to alleviate the problems caused by survey dates and intervals between surveys which do not coincide, covering international shipping regulations including the codes and conventions of these following institutions:
- International Convention for the Safety of Life at Sea (SOLAS), 1974
- The International Convention on Load Lines (LL), 1966
- The International Convention for the Prevention of Pollution from Ships, 1973, as modified by the Protocol of 1978 relating thereto –MARPOL 73/78
- The International Code for the Construction and Equipment of Ships Carrying Dangerous Chemicals in Bulk (IBC Code)
- Code for the Construction and Equipment of Ships Carrying Dangerous Chemicals in Bulk (BCH Code)
- Code for the Construction and Equipment of Ships Carrying Liquefied Gases in Bulk (IGC Code).
A standard interval of one year between harmonised surveys for ships which could be based on any of the followings :
- Initial survey – A complete inspection of all the items concerning the particular certificate before the ship is put into service to make sure they possess satisfactory conditions and are capable of carry out the service for which the ship is intended.
- Periodical survey – An official examination of the items relating to the particular certificate to ensure that they are meeting the requirements and are fit for the intended services.
- Renewal survey – As similar as the periodical survey but consequently results in issuing a new certificate.
- Intermediate survey – Inspection of specified items.
- Annual survey – General reviewing of the items concerned to the particular certificate to ascertain the fact that they have been observed maintained and remained fit for the service for which the ship is designated.
- Additional survey – General or partial Inspection, according to the circumstances, made after a repair resulting from casualty probes or whenever there is an important repair or renewal made.
A maximum period of validity of one year and five years for all passenger ship certificates and cargo ship certificates respectively.
Three months extension for cargo ship certificates on the harmonised survey system for ships and one month for short voyages. When the duration of a particular certificate is extended, the period of validity of new certificate begins from the expiry date of last certificate.
At least two inspections are required to be executed of the ship’s bottom in a five year period; maximum interval between the inspections has also been set at not more than thirty six months.
A substantive harmonised system for merchant marine which credits a combined cargo ship safety certificate to replace existing safety equipment, safety construction and safety radio certificates.
No more unscheduled inspections for harmonised system of classification for ships, while annual surveys have been made mandatory.