Merchant ships: construction and maintenance standards

Construction, radio and marine equipment standards for merchant ships and special shipping.


The construction and operation of merchant ships is controlled by a wide range of legislation. Many of these are based on international standards agreed by member states of the International Maritime Organization (IMO).

These IMO standards are usually agreed under European law before passing into UK legislation where amendments can be made. However, there are also other regulations related to specific vessel types.

This guide discusses the construction standards for merchant ships and special shipping, as well as standards for radio, navigation and marine equipment.

Merchant and special shipping construction standards

The construction of UK merchant ships is controlled by the Merchant Shipping (Cargo Ship Construction) Regulations 1997. This comprehensive legislation specifies construction standards, as well as safety issues ranging from bilge pumping to the prevention of fire hazards.

These construction standards form the basis on which merchant ships are surveyed and certificated. You can read more in Fishing vessels: classification, registration and inspection.

There are specialist construction standards which cover the different types of merchant vessel you may have. These include a code of practice for vessels engaged in oil recovery and specialist guidance on standards for the construction and operation of special ship types and offshore support vessels.

Radio and navigation equipment standards for merchant ships

Radio equipment on merchant ships is subject to the Merchant Shipping (Radio Installations) Regulations 1992 and 1998. It must conform to performance standards established by the IMO.

There are separate performance standards for very high-frequency radio, radio-telephones and radio telegraphy as well as for other equipment. There are also requirements under the 1992 regulations to meet the requirements of the Global Maritime Distress Safety Systems (GMDSS), including the provision of duplicate equipment and shore-based or on-board maintenance facilities.

Merchant ships must also comply with the requirements of the IMO Safety of Life at Sea (SOLAS) convention. To meet these requirements guidance is available for the installation of lighting systems and other navigation equipment using the most recent technology.

This ensures that vessels comply with SOLAS and the related International Regulations for Preventing Collisions at Sea.

Marine equipment standards

All electrical equipment used on merchant ships must be properly maintained. You should give particular consideration to the risks associated with vibration and mechanical shock. This applies to all electrical equipment including lighting, radios, navigational systems, operational machinery and safety systems.

Maintenance ensures the availability of equipment and prevents accidents from happening which result from loose connections or components.

Correct maintenance - including accurate record-keeping - is an important part of the ship’s statutory survey.

It is also recommended that up-to-date operating and maintenance manuals are made available on board ships and that they are provided in the working language used on the vessel.

Further information

Download Merchant Shipping Notice (MSN) 1671 (M) The Merchant Shipping (Cargo Ship Construction) (Amendment) Regulations 1999 from the Marine and Coastguard Agency (MCA) website (PDF, 314K)

Download MSN 1671 (M) Amendment 2 The Merchant Shipping (Cargo Ship Construction) Regulations 1997: Schedules from the MCA website (PDF, 562K)

Download MSN M1663 Vessels Engaged in Oil Recovery the MCA website (PDF, 112K)

Download Marine Guidance Note (MGN) 108 (M) Hull Stress Monitoring Systems from the MCA website (PDF, 144K)

Download MGN 390 (M) Construction Standards for Offshore Support Vessels and Other Special Ship Types from the MCA website (PDF, 296K)

Download MSN 1714 (M) Standards of Performance of Radio Equipment required by the Merchant Shipping (Radio Installations) Regulations 1998 from the Marine and Coastguard Agency (MCA) website (PDF, 577K)

Download MSN 1693 (M) Performance specifications required by the Merchant Shipping (Radio Installations) Regulations 1980 from the MCA website (PDF, 47K)

Download MSN 1690 (M) Serviceability and Maintenance Requirements of Radio Equipment under the GMDSS from the MCA website (PDF, 38K)

Download MGN 393 (M+F) Maintenance and the Use of New Technology Light Sources as Navigation Lights on SOLAS and non-SOLAS Vessels from the MCA website (PDF, 250K)

Download MGN (MGN) 132 (M+F) Electrical Equipment, Maintenance and Incidents from the MCA website (PDF, 451K)

Download Marine Information Note (MIN) 312 (M+F) Shipboard Operating and Maintenance Manuals from the MCA website (PDF, 264K)

Published 18 September 2012