Rules for Classification of Sea-going Steel Ships (2023 Amendments) will take effect on 1 July 2023.

Main contents of revisions are as follows:

PART ONE  PROVISIONS OF CLASSIFICATION

Add that where hydraulic test is difficult to be carried out on the shipway or within the dock, it may be carried out while the ship is afloat; adding the List of Certification Requirements for Natural Gas Specialized Products; adding the class notations R1(D)/R2(D)/R3(D) for ships engaged on non-international voyages in restricted service, NEV Carriage (X) for carriage of new energy vehicles, DGP-F for fire-fighting of dangerous goods in packaged form and Bow Loading System* for bow loading system; revising the class notation OMBO (One Man Bridge Operation) as BDE-1/BDE-2/BDE-3 (Bridge design and equipment), moving the class notations related to green eco-ships from Table I-3 to Table G; specifying that the intact stability, subdivision and damage stability, fire safety of ships in restricted service are to comply with the relevant requirements in PART TEN of the Rules. For ships under construction, the approved plans will not be invalid automatically after 4 years since the approval date of plans. UR Z17(Rev.17 202207) is included and relevant reference documents are updated. Revising the relevant requirements for inflatable rescue boat as well as the certification condition in the Approval and Certification Process. Deleting all contents related to green eco-ships. For relevant requirements, refer to CCS Rules for Green Eco-Ships (2022). 

PART TWO  HULL

Adding the transition scenario where taper is not necessary for the butting of plates of different thicknesses and that single-sided continuous fillet welding may be acceptable for dry spaces in superstructure and deckhouse; adding the strength requirement target when additional transverse strengthening in the form of transverse wash bulkheads or web frames is provided; specifying the boundary conditions for hatch cover FE model; specifying the compulsory scope for strengthened for heavy cargoes to be loading rate no greater than 0.833m³/t and that strengthening loaded by steel coils are excluded; optimizing the structural strength requirements for ships loaded with steel coils comprehensively, specifying strengthening scope, corrosion addition and revising requirements for inner bottom platings and stifeners as well as bilge hopper sloping plates; specifying the design load and stress criteria for the calculation of hull supporting structure for life-saving appliances; adding the definition for launch barge and the class notation requirement; adding the empirical formulae for the dynamic load of deck hinges and specifying the amplification factor; adjusting the arrangement requirement for deck girders in double box trunk deck.

PART THREE  MACHINERY INSTALLATIONS

Adding the selection requirements for test specimens with fire endurance for plastic piping systems on ships, and specifying means to carry out fire endurance tests; adding the measurement requirement for slope at stern bearing in shaft alignment steps after the integrated stern tubes are poured and installed; optimizing the definition of steering gear control system and adding the definition of hydraulic locking; clarifying the means of intervention for mechanical failures; adding the requirement for driving loads for the design load of windlasses and technical requirements for control brakes.

PART FOUR  ELECTRICAL INSTALLATIONS

Clarifying the ship types for which analysis for coordination of protective devices is required to be submitted; revising the provisions for alarm and automatic shutdown of ventilation fans and oil pumps before the release of fire extinguishing media; revising limits of Temperature Rise of Air-Cooled Machines; adding the provisions for explosion groups and temperature class for the carriage of some dangerous goods.

PART EIGHT  ADDITIONAL REQUIREMENTS

Adding the class notations for OMBO, i.e. BDE-1, BDE-2 and BDE-3, are revised and technical requirements for class notations BDE-2 and BDE-3; clarifying the unspecific parts in the existing rules in Chapter 15 Additional Requirements for Electrically Propelled Ships; deleting the additional requirements for passenger ships; specifying the requirements for fire-extinguishing systems and means of cooling; supplementing the technical requirements for the Bow Loading System*.

PART NINE  COMMON STRUCTURAL RULES FOR BULK CARRIERS AND OIL TANKERS

Revising the scope of application as determination upon the freeboard length; supplementing the requirements for the bow structure for local bow impact angle less than 50 deg; clarifying the rule requirements applicable to brackets of the superstructure and deckhouse; clarifying the value selection location for plate thickness due to correction of shear force of oil tankers; clarifying that the slenderness requirement is not applicable to bilge plates, corrugation and superstructures as well as deckhouses; specifying the means of handling when the flange width of the stiffener outstands; specifying the buckling assessment method of the primary supporting member in way of the opening; revising the calculation requirement for the ultimate buckling capacity of the stiffener; clarifying the dimensional requirements for members of superstructures and deckhouses; clarifying the relevant requirements for the hatch cover FE model.

PART TEN  SHIPS IN RESTRICTED SERVICE

Adding the class notations R1(D), R2(D) and R3(D) for ships engaged on non-international voyages in restricted service as well as requirements for survey after construction; adding the requirements for checking the longitudinal strength of ships assigned with different notations for transiting and operation respectively; deleting the requirements for survey of ‘tween deck of bulk carriers and chemical tankers.

Note: In the amendments, blue underline is to highlight new insertions, strikethrough line is to highlight deleted contents.