This Rule Note gives the requirements for construction and classification of harbour equipment intended to be operated as floating dock, floating bridge, floating door and other storage or working unit floating in smooth stretches of waters. NR612 is to be applied for structural elements of the hull and for components of the machinery and electrical installations of harbour equipment.
Main changes in NR612 – Rules for the classification of Harbour Equipment
1. Harmonisation of Rules’ content, structure, wording and terminology with NR217 Rules for
the classification of inland vessels.
2. Extension of Rules application to hull materials other than steel: aluminium (A), composite
(C), wood (W) and concrete (CR).
Classification and Surveys – PART A
1. Implementation of a new service notation “Floating plant” together with related additional
service features defining the plant type
2. Implementation of new additional service features for units:
– operated in “non-smooth” stretches of water
– using low flashpoint liquid or gas fuels
– fitted with fuel cells
3. Implementation of new additional class notations Battery system and Electric hybrid
4. Implementation of in service-survey requirements for:
– Service notation Floating plant
– additional service features related to hull materials A, C, W
– additional service features applicable to units using low flashpoint liquid or gas fuels
– additional service features applicable to units fitted with fuel cells
– additional class notations Battery system and Electric hybrid
5. Implementation of additional survey requirements for notations as a separate new Section
6. Cancellation of confirmation of term survey
Hull Design and Construction – PART B
1. DIN 18800 made the only buckling strength reference for all structural items, except pillars
2. Revision of the requirements for hull girder global strength analysis
3. Revision of the requirements for hull scantling
4. Implementation of strength check criteria for supporting structure of hull equipment
5. Implementation of strength check criteria for lifting appliances – hull connections
6. Revision of the requirements related to hull construction and testing.
Machinery, Systems and Electricity – PART C
Part organised in only one Section limited to harbour equipment specificities.
Additional Requirements for Notations – PART D
1. Requirements for hull outfitting moved to- and gathered in Part B, Chap 5, Sec 3.
2. Requirements for load model moved to- and gathered in Part B, Chap 4, Sec 1.
3. Implementation of a new Chapter containing technical requirements applicable to the new
service notation Floating plant.
4. Thorough revision of the requirements applicable to specific service notations.
In particular, thorough revision of the requirements applicable to floating docks including:
– Development of rule formulas for still water vertical hull girder loads
– Revision of the requirements for longitudinal hull girder & transverse strength assessment
(extension to all floating docks lifting capacity)
– Hull girder shear stresses have been taken into account for the scantling of plating subjected to
– Revision of stability design criteria and implementation of freeboard requirements.
5. Implementation of a new Section containing technical requirements applicable to harbour
equipment assigned operating area notation Hs<=x.
6. Harmonisation of the requirements applicable to additional class notation “Equipped for
wheeled vehicles” with NR217.
Download the rules: Rules for the Classification of Harbour Equipment