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Published Rules

This section defines the general principles used throughout Part 1. It explains the purpose of classification, the scope of application, the meaning of key terms, the relationship between rule documents, the responsibilities of involved parties, the effective date of requirements and the handling of information.The general principles shall be used when decid...

Published Version 1 Last updated 18 JUN 2026 10:02

Subsections

1.1 Purpose

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1.2 Scope and Application

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1.3 Definitions

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1.4 Rule Hierarchy and References

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1.5 Responsibilities of Parties

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1.6 Effective Date and Transitional Provisions

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1.7 Confidentiality and Information Sharing

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This section establishes the general application basis for Part 2 hull requirements. It defines how the hull rules are to be applied, how rule principles and assumptions are to be interpreted, which compliance evidence is required, which symbols and definitions are used, and how loading manuals and loading instruments support safe operation of the approved h...

Published Version 1 Last updated 18 JUN 2026 10:02

Subsections

1.1 Application

1.1.1 Scope of Application

1.1.1.1 General Scope

1.1.1.2 Structural and Material Basis

1.1.1.3 Special Designs and Alternative Arrangements

1.1.1.4 Scope Limitations

1.1.2 Rule Application

1.1.2.1 Application of Hull Requirements

1.1.2.2 Application by Ship Parts and Structural Items

1.1.2.3 Application of Specific and Additional Requirements

1.1.3 Relation to Other Rule Documents

1.1.3.1 Rule Document Hierarchy

1.1.3.2 Material and Fabrication Rules

1.1.3.3 Specific, Additional and Statutory Requirements

1.1.3.4 Conflict and Precedence

1.2 Rule Principles

1.2.1 Rule Objectives

1.2.1.1 Structural Safety

1.2.1.2 Protection of Life, Environment and Property

1.2.1.3 Durability During Design Life

1.2.1.4 Structural Integrity and Redundancy

1.2.1.5 Stability Where Applicable

1.2.2 General Assumptions

1.2.2.1 Scope of Structural Assessment

1.2.2.2 Design, Construction and Operation Assumptions

1.2.2.3 Operational Limits and Loading Conditions

1.2.2.4 Responsibilities and Additional Requirements

1.2.3 Design Basis

1.2.3.1 Design Parameters and Documentation

1.2.3.2 Hull Form Limits and Main Particulars

1.2.3.3 Design Life

1.2.3.4 Environmental Conditions

1.2.3.5 Operating Conditions and Design Draughts

1.2.3.6 Internal Environment and Cargo Conditions

1.2.3.7 Maximum Service Speed

1.2.3.8 Owner's Additional Requirements

1.2.4 Design Principles

1.2.4.1 Overall Design Principles

1.2.4.2 Limit State Design Principles

1.2.4.3 Design Load Scenarios

1.2.4.4 Structural Capacity Assessment

1.2.4.5 Net Scantling and Corrosion Basis

1.2.4.6 Intact and Damaged Structural Conditions

1.2.5 Rule Design Methods

1.2.5.1 General Design Methods

1.2.5.2 Working Stress Design Method

1.2.5.3 Partial Safety Factor Method

1.2.5.4 Minimum Requirements

1.2.5.5 Load-Capacity Based Requirements

1.2.5.6 Acceptance Criteria

1.2.5.7 Design Verification

1.3 Verification of Compliance

1.3.1 Documentation for Design Assessment

1.3.1.1 Scope of Submitted Documentation

1.3.1.2 Plans, Drawings and Calculations

1.3.1.3 Approval and Information Documents

1.3.1.4 Additional or Supplementary Documentation

1.3.1.5 Changes to Approved Design Documentation

1.3.2 Required Compliance Documentation

1.3.2.1 General Requirement for Compliance Documents

1.3.2.2 Material and Product Certificates

1.3.2.3 Equipment and System Compliance Documents

1.3.2.4 Issuer, Standard and Traceability

1.3.2.5 Availability and Submission of Compliance Evidence

1.3.3 Survey, Inspection and Testing Requirements

1.3.3.1 Scope of Surveys, Inspections and Tests

1.3.3.2 Attendance and Access for Survey

1.3.3.3 Testing and Examination Requirements

1.3.3.4 Non-Conformities and Corrective Actions

1.3.3.5 Acceptance of Survey, Inspection and Test Results

1.3.4 Equivalence and Alternative Methods

1.3.4.1 Submission of Alternative Proposals

1.3.4.2 Demonstration of Equivalence

1.3.4.3 Additional Verification and Testing

1.3.4.4 Scope and Conditions of Acceptance

1.4 Symbols and Definitions

1.4.1 Symbols and Units

1.4.1.1 Ship Dimensions and Main Data

1.4.1.2 Material Symbols

1.4.1.3 Load Symbols

1.4.1.4 Scantling and Structural Symbols

1.4.1.5 General Constants and Units

1.4.2 Principal Definitions

1.4.2.1 Rule Length

1.4.2.2 Load Line and Subdivision Lengths

1.4.2.3 Moulded Breadth and Moulded Depth

1.4.2.4 Draughts

1.4.2.5 Coefficients

1.4.2.6 Lightweight and Deadweight

1.4.2.7 Ends and Midship

1.4.3 Operation and Loading Definitions

1.4.3.1 Loading Condition

1.4.3.2 Design Loading Condition

1.4.3.3 Actual Loading Condition

1.4.3.4 Departure, Arrival and Intermediate Conditions

1.4.3.5 Seagoing Condition

1.4.3.6 Harbour and Sheltered Water Condition

1.4.3.7 Cargo, Ballast and Special Loading Conditions

1.4.3.8 Partially Filled Tank Condition

1.4.3.9 Ballast Water Exchange and Tank Testing Condition

1.4.3.10 Design Load Scenario

1.4.3.11 Operational Limitation

1.5 Loading Manual and Loading Instruments

1.5.1 Loading Manual Requirement Criteria

1.5.1.1 General Requirement for Approved Loading Manual

1.5.1.2 Length and Category Criteria

1.5.1.3 Category II Exception

1.5.1.4 Loading Instrument Requirement

1.5.1.5 Ship-Type and Notation Specific Requirements

1.5.1.6 Existing Ship and Retroactive Requirement Considerations

1.5.2 Loading Manual

1.5.2.1 Content of Loading Manual

1.5.2.2 Loading Conditions to be Included

1.5.2.3 Operational Limitations

1.5.2.4 Still Water Bending Moment and Shear Force Limits

1.5.2.5 Local Loading Limits

1.5.2.6 Approval Basis and Updates

1.5.2.7 Language and Availability

1.5.3 Loading Instrument

1.5.3.1 Definition and Scope

1.5.3.2 Ship-Specific Approval

1.5.3.3 Strength and Stability Functions

1.5.3.4 Operation Manual for Loading Instrument

1.5.3.5 Test Conditions and Onboard Verification

1.5.3.6 Tolerances and Acceptance of Results

1.5.3.7 Software Modifications and Updates

1.5.3.8 Periodical Testing and Records

1.5.3.9 Documents to be Kept On Board

This section defines the structural design principles for the hull structure. The requirements establish how plating, stiffeners, primary supporting members, structural details, openings, local reinforcements and special arrangements shall be arranged so that loads are transmitted safely through the hull structure.The structural design principles shall be ap...

Published Version 1 Last updated 18 JUN 2026 10:02

Subsections

2.1 General Structural Design Basis

2.1.1 Design Basis and Structural Function

2.1.2 Load Path and Structural Response

2.1.3 Structural Members and Support System

2.1.4 Design Verification Basis

2.1.5 Limits of General Structural Design Basis

2.2 Structural Continuity

2.2.1 General Continuity Requirement

2.2.2 Continuity at Member Terminations

2.2.3 Continuity in Transition Zones

2.2.4 Longitudinal Strength Members

2.2.4.1 General Requirement

2.2.4.2 Extent of Longitudinal Strength Members

2.2.4.3 Continuity at Transverse Members and Bulkheads

2.2.4.4 Alternative Arrangements and Verification

2.2.5 Compensation at Openings and Interruptions

2.2.5.1 General Requirement

2.2.5.2 Openings in Stiffeners and Primary Supporting Members

2.2.5.3 Openings in Decks, Shell Plating and Longitudinal Bulkheads

2.2.5.4 Reinforcement and Compensation Around Openings

2.2.5.4.1 Edge Reinforcement

2.2.5.4.2 Insert Plates and Compensation Plates

2.2.5.4.3 Shell Openings and Local Compensation

2.2.5.4.4 Compensation by Direct Assessment

2.2.5.4.5 Hatch Corner Insert Plates

2.2.5.5 Large Openings and Special Consideration

2.2.5.5.1 Small Openings and Spacing in Strength Deck

2.2.5.5.2 Large Openings and Effective Shear Area

2.2.5.5.3 Secondary Bending Around Large Openings

2.2.6 Gradual Transition of Plate Thickness and Section Properties

2.2.6.1 General Transition Requirement

2.2.6.2 Plate Thickness Transition

2.2.6.3 Insert Plate and Taper Length

2.2.6.4 Face Plate and Flange Width Transition

2.2.6.5 Transition of Longitudinal Strength Members

2.2.6.6 Verification in High Stress Areas

2.2.6.7 Transition Between Different Materials

2.3 Primary Supporting Structure

2.3.1 General Arrangement of Primary Supporting Members

2.3.2 Floors, Girders and Web Frames

2.3.3 Web Stiffeners of Primary Supporting Members

2.3.3.1 General Arrangement of Web Stiffeners

2.3.3.2 Web Stiffeners in High Shear Areas

2.3.3.3 Web Stiffeners Around Openings and Cut-outs

2.3.3.4 Connection of Web Stiffeners to Intersecting Members

2.3.3.4.1 General Connection Principle

2.3.3.4.2 Load Transmitted Through Shear Connection

2.3.3.4.3 Load Transmitted Through PSM Web Stiffener

2.3.3.4.4 Lug Plates, Collar Plates and Backing Brackets

2.3.3.4.5 Stress Checks and Acceptance

2.3.3.5 Web Stiffeners Subject to Fatigue or Direct Stress

2.3.3.5.1 Fatigue-Sensitive and High Direct Stress Locations

2.3.3.5.2 Soft Heel and Keyhole Arrangements

2.3.3.5.3 Offset PSM Web Stiffeners

2.3.3.5.4 Fillet Weld Sizing for Web Stiffener Connections

2.3.3.5.5 Openings, Scallops and Drain Holes in Fatigue-Sensitive Areas

2.3.4 Tripping Brackets and Lateral Support

2.3.4.1 General Arrangement of Tripping Brackets

2.3.4.2 Locations Requiring Tripping Brackets

2.3.4.3 Support of Wide Face Plates

2.3.4.4 Arm Length of Tripping Brackets

2.3.4.5 Backing Brackets and Tripping Flat Bars

2.3.5 End Connections of Primary Supporting Members

2.3.5.1 General End Connection Requirements

2.3.5.2 Scantling of End Brackets

2.3.5.3 Arrangement of End Brackets

2.3.5.4 Bracket Toes and Face Plate Termination

2.3.5.5 Special Considerations for Fatigue and Higher Strength Steel

2.3.6 Bracketless Connections

2.3.6.1 General Bracketless Connection Requirements

2.3.6.2 Bracketless Crossing Between Two Primary Supporting Members

2.3.6.3 Bracketless Crossing Between Three Primary Supporting Members

2.3.6.4 Cross-Joint Web Thickness and Flange Force Transfer

2.3.6.5 Stiffening, Buckling and Lamellar Tearing Considerations

2.3.7 Pillars and Cross Ties

2.3.7.1 General Arrangement of Pillars and Cross Ties

2.3.7.2 Support and Load Distribution at Heads and Heels

2.3.7.3 Pillars in Tanks and Special Spaces

2.3.7.4 Pillar Strength and Buckling Assessment

2.3.7.5 Contact Pressure at Pillar Connections

2.3.7.6 Doubling Plates, Insert Plates and Tensile Load Connections

2.3.8 Primary Supports for Bulkheads and Corrugated Bulkheads

2.3.8.1 Bulkheads Acting as Primary Supports

2.3.8.2 Stool Structures and End Support of Corrugated Bulkheads

2.3.8.3 Corrugation Geometry and Construction

2.3.8.4 Corrugation Depth and Effective Span

2.3.8.5 Section Modulus of Corrugations

2.3.8.6 Support Continuity, Diaphragms and Local Reinforcement

2.3.9 Verification of Primary Supporting Members

2.3.9.1 General Verification Requirements

2.3.9.2 Net Scantling and Corrosion Basis

2.3.9.3 Yield and Shear Stress Verification

2.3.9.4 Buckling Verification

2.3.9.5 Direct Strength and Finite Element Assessment

2.3.9.6 Fatigue-Sensitive and High Stress Details

2.3.9.7 Verification of Alternative Arrangements

2.3.9.8 Acceptance Criteria for Primary Supporting Members

2.3.9.8.1 General Application of Acceptance Criteria

2.3.9.8.2 Permissible Normal and Shear Stress

2.3.9.8.3 Combined Stress and Utilisation Check

2.3.9.8.4 Buckling Acceptance Criteria

2.3.9.8.5 Deformation and Stiffness Criteria

2.3.9.8.6 Fatigue Acceptance Criteria

2.3.9.8.6.1 Fatigue Detail Categories

2.3.9.8.6.2 S-N Curves and Design Life

2.3.9.8.6.3 Stress Range and Cumulative Damage

2.3.9.8.7 Direct Strength and Finite Element Acceptance

2.3.9.8.8 Acceptance of Alternative Arrangements

2.4 Stiffening Arrangement

2.4.1 General Stiffener Arrangement

2.4.2 Stiffener Spacing and Supported Plating

2.4.3 Stiffener Continuity and Alignment

2.4.4 Stiffener End Support and Load Transfer

2.4.5 Stiffeners in Way of Openings and Discontinuities

2.4.6 Stiffeners in High Shear and Fatigue-Sensitive Areas

2.4.7 Longitudinal Stiffeners in Strength-Critical Regions

2.4.8 Transverse Stiffeners, Frames and Secondary Members

2.4.9 Special Stiffening Arrangements

2.5 Plating Arrangement

2.5.1 General Plating Arrangement

2.5.2 Plate Fields and Supported Panels

2.5.2.1 Plate Panel Boundaries and Support

2.5.2.2 Panel Aspect Ratio and Effective Dimensions

2.5.2.3 Unsupported Plate Fields and Additional Support

2.5.2.4 Buckling and Deformation of Supported Panels

2.5.2.5 Local Plate Bending and Direct Assessment

2.5.3 Plating Continuity and Plate Strakes

2.5.3.1 Strength Deck and Sheer Strake Plating

2.5.3.2 Shell, Bilge and Bottom Strakes

2.5.3.3 Longitudinal Bulkhead and Inner Bottom Plating

2.5.4 Plate Thickness Transitions

2.5.4.1 Thickness Change and Tapering

2.5.4.2 Insert Plates in Thickness Transitions

2.5.4.3 Transition in Strength-Critical Areas

2.5.5 Insert Plates, Doublers and Local Plate Reinforcement

2.5.5.1 Insert Plates

2.5.5.2 Doubling Plates

2.5.5.3 Local Reinforcement Around Concentrated Loads

2.5.6 Plating in Way of Openings and Discontinuities

2.5.6.1 Openings in Strength Deck and Shell Plating

2.5.6.2 Hatch Corners and Rounded Openings

2.5.6.3 Penetrations, Manholes and Access Openings

2.5.6.4 Compensation and Edge Reinforcement

2.5.7 Plating Subject to Local Loads

2.5.7.1 Wheel Loads and Vehicle Deck Plating

2.5.7.2 Cargo and Equipment Loads

2.5.7.3 Machinery Foundations and Local Attachments

2.5.7.4 Mooring and Towing Equipment Loads

2.5.8 Plating in Tanks and Corrosion-Prone Areas

2.5.8.1 Tank Boundary Plating

2.5.8.2 Drainage, Cleaning and Inspection Access

2.5.8.3 Corrosion Protection and Coating Support

2.5.9 Special Plating Arrangements

2.6 Structural Details and Connections

2.6.1 General Detailing Requirements

2.6.2 Welded Connections and Weld Details

2.6.2.1 General Welded Connection Requirements

2.6.2.2 Butt Welds and Full Penetration Welds

2.6.2.3 Fillet Welds and Effective Throat

2.6.2.4 Weld Terminations, Intersections and Access

2.6.2.5 Fatigue-Sensitive Weld Details and Inspection

2.6.3 Brackets, Tripping Brackets and End Terminations

2.6.3.1 General Bracket and End Termination Requirements

2.6.3.2 End Brackets and Bracket Arms

2.6.3.3 Tripping Brackets and Lateral Support

2.6.3.4 Bracket Toes, Face Plates and Soft Terminations

2.6.3.5 Brackets in Fatigue-Sensitive and High Stress Areas

2.6.4 Cut-outs, Slots, Scallops and Drain Holes

2.6.4.1 General Arrangement of Cut-outs and Slots

2.6.4.2 Web Slots and Stiffener Passages

2.6.4.3 Scallops, Weld Access Holes and Rat Holes

2.6.4.4 Drain, Air and Limber Holes

2.6.4.5 Reinforcement and Compensation Around Openings

2.6.4.6 Small Openings, Spacing and Local Loads

2.6.5 Lug Plates, Collar Plates and Backing Structure

2.6.5.1 General Arrangement of Lug Plates, Collar Plates and Backing Structure

2.6.5.2 Lug Plates and Local Load Attachments

2.6.5.3 Collar Plates Around Slots and Penetrations

2.6.5.4 Backing Brackets and Backing Structure

2.6.5.5 Welding, Fit-up and Inspection of Lug, Collar and Backing Details

2.6.5.6 Fatigue-Sensitive and High Stress Lug or Collar Details

2.6.6 Sniped Ends, Soft Toes and Local Terminations

2.6.6.1 General Requirements for Local Terminations

2.6.6.2 Sniped Ends of Stiffeners and Local Members

2.6.6.3 Soft Toes and Tapered Transitions

2.6.6.4 Terminations in Fatigue-Sensitive and High Stress Areas

2.6.7 Doublers, Inserts and Local Attachment Details

2.6.7.1 General Use of Doublers, Inserts and Local Attachments

2.6.7.2 Insert Plates and Structural Renewal Details

2.6.7.3 Doubler Plates and Their Limitations

2.6.7.4 Local Attachment Pads and Temporary Fittings

2.6.7.5 Welding, Inspection and Corrosion Control for Added Plates

2.6.8 Fatigue-Sensitive Details and Workmanship

2.6.8.1 General Fatigue-Sensitive Detailing Requirements

2.6.8.2 Weld Profile, Weld Toe and Weld Termination Quality

2.6.8.3 Geometry Transitions and Stress Concentration Control

2.6.8.4 Workmanship, Tolerances and Fabrication Control

2.6.8.5 Direct Assessment and Inspection of Critical Details

2.6.9 Inspection, Access and Corrosion-Avoiding Details

2.6.9.1 General Inspection and Access Requirements

2.6.9.2 Drainage, Ventilation and Air Escape

2.6.9.3 Coating Access and Avoidance of Corrosion Traps

2.6.9.4 Inspection of Welds, Edges and Local Attachments

2.6.9.5 Maintainability and Repair-Friendly Detailing

2.7 Openings, Knuckles and Discontinuities

2.7.1 General Arrangement of Openings and Discontinuities

2.7.2 Openings in Strength Deck, Shell and Longitudinal Members

2.7.3 Openings in Stiffeners and Primary Supporting Members

2.7.4 Hatch Corners, Rounded Openings and Corner Radii

2.7.5 Knuckles, Changes of Plane and Geometric Discontinuities

2.7.6 Penetrations, Manholes and Access Openings

2.7.7 Reinforcement, Compensation and Direct Assessment

2.7.8 Fatigue, Inspection and Corrosion Considerations

2.8 Local Reinforcement Principles

2.8.1 General Requirement for Local Reinforcement

2.8.2 Reinforcement Around Concentrated Loads and Attachments

2.8.3 Insert Plates and Increased Thickness Reinforcement

2.8.4 Doublers and Local Attachment Plates

2.8.5 Collar Plates, Lug Plates and Backing Structure

2.8.6 Edge Reinforcement and Ring Reinforcement

2.8.7 Reinforcement in Fatigue-Sensitive Areas

2.8.8 Verification of Local Reinforcement

2.9 Special Structural Arrangements

2.9.1 General Requirement for Special Structural Arrangements

2.9.2 Non-Standard Load Paths and Structural Interaction

2.9.3 Large Local Structural Discontinuities

2.9.4 Movable, Removable or Intermittently Supported Structures

2.9.4.1 Movable or Removable Deck Structures

2.9.4.2 Ramps, Doors and Supporting Boundaries

2.9.4.3 Locking, Seating and Support Points

2.9.5 Special Foundations and Equipment Support Arrangements

2.9.5.1 Heavy Equipment and Machinery Foundations

2.9.5.2 Deck Machinery and Fitting Supports

2.9.5.3 Vibration and Fatigue-Sensitive Supports

2.9.6 Structural Arrangements for Special Spaces

2.9.6.1 Vehicle Decks and Ro-Ro Spaces

2.9.6.2 Cargo Holds and Special Cargo Support Areas

2.9.6.3 Machinery and Service Spaces

2.9.7 Mixed or Unusual Structural Materials and Interfaces

2.9.8 Verification and Acceptance of Special Structural Arrangements

This section defines the design loads to be used for hull structural assessment, including static loads, dynamic loads, hull girder loads, external sea pressures, internal pressures, cargo loads, local loads and design load scenarios. The design loads shall be selected so that the relevant operating conditions, loading conditions, draughts, ship motions, acc...

Published Version 1 Last updated 18 JUN 2026 10:02

Subsections

3.1 General Load Principles

3.1.1 Scope and Application

3.1.2 Static and Dynamic Load Components

3.1.3 Strength and Fatigue Load Basis

3.1.4 Load Combination Principles

3.2 Coordinate System, Motions and Accelerations

3.2.1 Coordinate System and Sign Convention

3.2.2 Ship Motions

3.2.3 Accelerations at Centre of Gravity

3.2.4 Accelerations at Any Position

3.2.5 Hull Girder Load Sign Convention

3.3 Hull Girder Loads

3.3.1 Application and Load Basis

3.3.2 Still Water Hull Girder Loads

3.3.2.1 Still Water Loading Conditions and Envelopes

3.3.2.2 Vertical Still Water Bending Moment

3.3.2.3 Vertical Still Water Shear Force

3.3.2.4 Still Water Torsional Moment

3.3.3 Wave Hull Girder Loads

3.3.3.1 Vertical Wave Bending Moment

3.3.3.2 Vertical Wave Shear Force

3.3.3.3 Horizontal Wave Bending Moment

3.3.3.4 Horizontal Wave Shear Force

3.3.3.5 Wave Torsional Moment

3.3.4 Hull Girder Loads for Dynamic Load Cases

3.3.4.1 Vertical Bending Moment for Dynamic Load Cases

3.3.4.2 Vertical Shear Force for Dynamic Load Cases

3.3.4.3 Horizontal Bending and Shear for Dynamic Load Cases

3.3.4.4 Torsional Moment for Dynamic Load Cases

3.3.5 Reporting and Verification of Hull Girder Load Data

3.3.5.1 Hull Girder Load Data Submission and Verification

3.4 External Loads

3.4.1 Application and External Load Basis

3.4.2 Hydrostatic Pressure on Shell

3.4.3 Wave Pressure on Shell

3.4.4 External Pressure for Fatigue Assessment

3.4.5 Loads on Exposed Decks and Green Sea

3.4.6 Loads on Superstructures and Deckhouses

3.4.7 Impact and Slamming Loads

3.4.8 Local External Loads on Openings, Doors and Sea Chests

3.5 Internal Loads and Cargo Loads

3.5.1 Application and Internal Load Basis

3.5.2 Liquid Loads in Tanks and Ballast Holds

3.5.3 Partly Filled Tanks, Sloshing and Impact

3.5.4 Flooding, Tank Testing and Overfilling Loads

3.5.5 Dry Bulk Cargo Loads

3.5.6 Deck, Platform and Unit Cargo Loads

3.5.7 Wheeled Cargo and Container Loads

3.5.8 Hatch Cover, Coaming and Special Cargo Loads

3.6 Design Load Scenarios

3.6.1 Scenario Classification and Load Categories

3.6.2 Principal Strength Design Load Scenarios

3.6.3 Load Component Matrix for Strength Assessment

3.6.4 Impact and Sloshing Design Load Scenarios

3.6.5 Fatigue Design Load Scenario

3.6.6 Design Load Sets for Local and Primary Structure

3.6.7 Scenario Selection and Documentation

3.6.8 Governing Scenario Selection and Completeness Check

3.7 Loading Conditions and Operational Limits

3.7.1 Application and Loading Condition Basis

3.7.2 Standard Seagoing and Harbour Loading Conditions

3.7.3 Partly Filled Tanks and Ballast Conditions

3.7.4 Cargo Loading Patterns and Ship-Type Conditions

3.7.5 Permissible Hull Girder and Local Load Limits

3.7.6 Loading Manual and Loading Instrument Requirements

3.7.7 Operational Restrictions and Approval of Loading Conditions

This section defines the requirements for finite element analysis of hull structures. Finite element analysis shall be used where direct structural response, primary supporting member behaviour, local stress concentration, buckling verification, fatigue assessment or special load effects cannot be adequately verified by prescriptive formulae alone. The FE an...

Published Version 1 Last updated 18 JUN 2026 10:02

Subsections

8.1 Application and Analysis Levels

8.1.1 Global FE Analysis

8.1.2 Partial Ship and Cargo Hold FE Analysis

8.1.3 Local Fine Mesh and Sub-model Analysis

8.1.4 Fatigue Hot Spot and Direct Fatigue FE Analysis

8.1.5 Non-linear and Special FE Analysis

8.2 Model Extent and Structural Idealisation

8.2.1 Members, Openings and Simplifications

8.2.2 Stiffeners, Girders, Pillars and Foundations

8.3 Material, Thickness and Corrosion Basis

8.4 Element Types, Mesh Arrangement and Mesh Quality

8.4.1 Global and Standard Mesh Requirements

8.4.2 Fine Mesh and Transition Requirements

8.5 Boundary Conditions and Load Application

8.5.1 Hull Girder and Local Load Combination

8.5.2 Boundary Transfer for Local Models

8.6 Result Extraction and Stress Assessment

8.6.1 Yielding and Von Mises Stress Assessment

8.6.2 Buckling Result Extraction

8.6.3 Fatigue and Hot Spot Result Extraction

8.7 Acceptance Criteria and Utilization Checks

8.8 Documentation and Review Package

8.9 Relationship with Other Strength Clauses

This section defines the structural and functional requirements for hull equipment and appendages fitted to or supported by the hull structure. It covers appendages and equipment whose loads, supports, attachments, closing arrangements or maintenance condition may affect hull strength, watertight or weathertight integrity, operational safety, corrosion prote...

Published Version 1 Last updated 18 JUN 2026 10:02

Subsections

11.1 Application and Equipment Basis

11.2 Rudders, Rudder Horns and Steering Appendages

11.2.1 Application, Arrangement and Submitted Data

11.2.2 Rudder Forces, Torque and Load Cases

11.2.3 Rudder Stock, Tiller Region and Deformation Control

11.2.4 Couplings, Bolts, Keys and Locking Devices

11.2.5 Pintles, Bearings, Clearances and Bearing Pressure

11.2.6 Rudder Blade Plating, Webs and Internal Structure

11.2.7 Rudder Horns, Solepieces and Hull Support Connection

11.2.8 Steering Nozzles and Special Steering Appendages

11.2.9 Materials, Welding, NDT, Testing and Records

11.3 Propeller Shaft Brackets, Bossings, Thrusters and Sea Chests

11.3.1 Application, Arrangement and Submitted Data

11.3.2 Propeller Shaft Bossing and Stern Tube Support

11.3.3 Propeller Shaft Brackets and Bracket Arm Attachments

11.3.4 Thruster Tunnels, Sea Chests and Inlet/Outlet Structures

11.3.5 Azimuth, Podded and Thruster Hull Supports

11.3.6 Materials, Welding, Testing and Records

11.4 Bilge Keels, Skegs, Fins and External Appendages

11.4.1 Application, Arrangement and Submitted Data

11.4.2 Bilge Keel Material, Arrangement and Ground Bar

11.4.3 Bilge Keel Ends, Tapering and Crack-Arrest Details

11.4.4 Bilge Keel Welding, Butt Location and NDT

11.4.5 Skegs, Fins and External Appendage Supports

11.4.6 Stabilizer Recesses, Fin Openings and Local Shell Compensation

11.4.7 Hydrodynamic, Fatigue and Vibration Assessment of Appendages

11.4.8 Inspection, Damage, Repair and Records

11.5 Bulwarks, Guard Rails, Freeing Ports and Deck Safety Fittings

11.5.1 Application, Arrangement and Submitted Data

11.5.2 General Protection Height and Open-Rail Requirements

11.5.3 Bulwark Construction, Plating and Stays

11.5.4 Freeing Ports and Deck Drainage

11.5.5 Freeing Port Closures, Shutters and Icing Conditions

11.5.6 Guard Rails, Stanchions and Openings

11.5.7 Sheer Strake, Stringer Plate and Local Attachment Restrictions

11.5.8 Deck Safety Fittings, Fairleads, Hawse Holes and Special Loads

11.5.9 Inspection, Maintenance and Survey Follow-up

11.6 Anchoring Equipment, Hawse Pipes and Chain Lockers

11.6.1 Application, Equipment Schedule and Submitted Data

11.6.2 Equipment Number and Anchoring Arrangement Basis

11.6.3 Anchors, Chain Cables, Attachment Pieces and Inboard Ends

11.6.4 Hawse Pipes, Anchor Pockets and Chain Lead

11.6.5 Windlass, Chain Stopper and Supporting Structure

11.6.6 Chain Lockers, Spurling Pipes, Drainage and Access

11.6.7 Local Loads, Corrosion Exposure and Structural Reinforcement

11.6.8 Testing, Marking, Inspection and Maintenance Records

11.6.9 Special Arrangements, Alternative Equipment and Service Limitations

11.7 Mooring, Towing and Emergency Towing Arrangements

11.7.1 Application, Submitted Data and Arrangement Plan

11.7.2 Mooring and Towing Design Load Basis

11.7.3 Shipboard Fittings, Line Leads and Load Application

11.7.3.1 Resultant Load at Fairleads and Line Direction Changes

11.7.3.2 SWL, TOW and Fitting Marking

11.7.4 Supporting Hull Structure and Foundations

11.7.4.1 Net Scantling, Corrosion and Wear Basis

11.7.4.2 Stress Acceptance and Structural Continuity

11.7.5 Mooring Winches, Capstans and Deck Machinery Foundations

11.7.6 Emergency Towing Arrangements

11.7.6.1 Emergency Towing Components and Deployment

11.7.6.2 Emergency Towing Strength and Geometry Criteria

11.7.7 Testing, Marking, Inspection and Maintenance Records

11.7.8 Special Arrangements, Limitations and Non-Standard Uses

11.8 Shell Doors, Hatches, Ramps and Closing Appliances

11.8.1 Application, Submitted Documents and Arrangement Basis

11.8.2 Boundary Integrity, Tightness and Closing Function

11.8.3 Design Loads and Structural Assessment Basis

11.8.4 Hatch Covers, Coamings and Hatch Supporting Structure

11.8.5 Shell Doors, Side Doors, Stern Doors and Bow Doors

11.8.6 Ramps, Movable Decks and Vehicle Access Arrangements

11.8.7 Securing, Locking, Supporting and Indicating Devices

11.8.8 Sealing, Drainage, Gaskets and Water Ingress Control

11.8.9 Testing, Operation, Maintenance and Survey Records

11.8.10 Special Arrangements, Existing Ships and Service Limitations

11.9 Helicopter Decks, Lifting Appliance Foundations and Local Deck Equipment

11.9.1 Application, Submitted Documents and Arrangement Basis

11.9.2 Helicopter Deck Structural Arrangement and Load Basis

11.9.3 Helicopter Landing Area, Safety Net and Local Deck Details

11.9.4 Lifting Appliance Foundations and Crane/Pedestal Supports

11.9.4.1 Lifting Geometry, Radius and Boom Angle

11.9.4.2 Wire, Sling and Spreader Load Effects

11.9.4.3 Foundation Reactions from Lifting Geometry

11.9.4.4 Proof Load, Dynamic Factor and Service Limitations

11.9.5 Deck Machinery, Local Equipment Seats and Attachments

11.9.6 Load Transfer, Reinforcement and Supporting Hull Structure

11.9.7 Fatigue, Vibration and Operational Dynamic Effects

11.9.8 Testing, Marking, Operation and Maintenance Records

11.9.9 Special Arrangements, Temporary Equipment and Service Limitations

11.10 Testing, Manuals, Inspection and Maintenance Records

This section defines ship type specific hull requirements to be applied in addition to the general Part 2 hull requirements. Ship type specific requirements may be necessary where the cargo type, loading mode, tank or hold arrangement, vehicle operation, passenger or service arrangement, special equipment, operating profile or service notation creates struct...

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Subsections

12.1 Application of Ship Type Specific Requirements

12.2 Bulk Carriers, Ore Carriers and Heavy Cargo Ships

12.2.1 Application, Cargo Loading Basis and Ship Data

12.2.2 Cargo Holds, Hatch Covers and Local Hold Structure

12.2.3 Alternate Loading, Heavy Cargo and Loading Manual Limits

12.3 Tankers and Ships with Liquid Cargo Tanks

12.3.1 Tank Arrangement and Boundary Structure

12.3.2 Liquid Cargo Loads, Sloshing and Tank Testing

12.3.3 Corrosion Protection, Coating, Drainage and Access

12.4 Container Ships and Ships Carrying Containers

12.4.1 Container Loading, Stack Loads and Securing Basis

12.4.2 Hatch Covers, Coamings and Large Deck Openings

12.4.3 Torsion, Hull Girder Response and Direct Assessment

12.5 Ro-Ro Cargo Ships, Vehicle Carriers and Ferries

12.5.1 Vehicle Decks, Wheel Loads and Securing Loads

12.5.2 Ramps, Movable Decks, Shell Openings and Closing Appliances

12.5.3 Operational Restrictions, Loading Patterns and Survey Access

12.6 Passenger Ships and Ships with Accommodation or Service Spaces

12.6.1 Passenger and Accommodation Structural Interfaces

12.6.2 Openings, Penetrations and Concealed Structure

12.7 Tugs, Workboats and Service Craft

12.7.1 Towing, Pushing and Working Load Basis

12.7.2 Fendering, Contact Loads and Local Operational Damage

12.8 Barges, Pontoons and Non-Propelled Units

12.8.1 Deck Cargo, Uniform Loads and Restricted Service Basis

12.8.2 Support, Mooring and Local Reinforcement of Non-Propelled Units

12.9 Special Purpose, Offshore Support and Unusual Ships

12.9.1 Mission Equipment, Special Foundations and Unusual Load Paths

12.9.2 Case-by-Case Direct Assessment and Service Limitations

12.10 Documentation, Loading Manual and Operational Limitations

12.10.1 Ship Type Specific Submission and Loading Documentation

12.10.2 Loading Manual, Loading Instrument and Operational Restrictions

12.10.3 Records, Survey Follow-up and Change Control

This section establishes the general application basis for Part 3 machinery requirements. It defines the machinery installations covered by this part, the meaning of essential machinery services, the arrangement assumptions used for machinery approval, the document basis for review, and the interfaces that must be coordinated with other rule parts and statut...

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Subsections

1.1 Application

1.1.1 Ships and Machinery Installations Covered

1.1.2 Systems Covered by Part 3

1.1.3 Approval Boundary and Excluded Scope

1.1.4 Application to Construction, Conversion and Repair

1.1.5 Statutory, Notation and Special Service Additions

1.2 Definitions and Essential Services

1.2.1 Machinery Terms

1.2.2 Essential Service Categories

1.2.3 Redundancy, Standby and Availability Terms

1.2.4 Failure Consequence Classification

1.2.5 Records and Interpretation of Definitions

1.3 Machinery Arrangement Basis

1.3.1 Machinery Space Layout and Service Separation

1.3.2 Foundations, Supports and Load Transfer

1.3.3 Access, Maintenance and Survey Clearance

1.3.4 Ventilation, Drainage and Leakage Control

1.3.5 Protection, Interfaces and Operating Limitations

1.4 Submitted Documents

1.4.1 Document Scope and Submission Register

1.4.2 Plans, Drawings and Calculations

1.4.3 Manufacturer Data, Certificates and Material Evidence

1.4.4 Control, Safety and Test Documentation

1.4.5 As-Built, Change and Onboard Records

1.5 Interface with Other Rule Parts

1.5.1 Hull Structure, Foundations and Alignment Interface

1.5.2 Electrical, Control and Automation Interface

1.5.3 Fire Safety, Statutory and Notation Interface

1.5.4 Testing, Survey and Records Interface

1.5.5 Interface Conflicts, Changes and Open Items

1.6 Machinery Compliance Records

1.7 Alternative and Novel Machinery Arrangements

This section defines the machinery documentation, approval and evidence requirements used to review machinery systems before manufacture, installation, commissioning, trials and service. The submitted information shall be sufficient to verify design suitability, safety function, essential-service availability, redundancy, maintainability, surveyability, test...

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Subsections

2.1 Approval Scope and Document List

2.1.1 Approval Scope Identification

2.1.2 Document Register and Approval Category

2.1.3 Machinery System Boundary and Interfaces

2.1.4 Initial, Supplementary and Revised Submissions

2.1.5 Open Items, Limitations and Close-Out Basis

2.2 Calculation and Analysis Basis

2.2.1 Calculation Scope, Inputs and Assumptions

2.2.2 Load Cases, Ratings and Operating Conditions

2.2.3 Shafting, Vibration and Alignment Analysis

2.2.4 Pressure, Thermal, Flow and Hydraulic Analysis

2.2.5 Control, Software, Simulation and Validation Evidence

2.2.6 Acceptance, Reporting and Revision Traceability

2.3 Manufacturer Data and Certification

2.3.1 Manufacturer Identity, Rating and Data Sheet

2.3.2 Certification Route and Document Type

2.3.3 Material, Component and Serial Traceability

2.3.4 Manufacturing Inspection, Tests and NDT Evidence

2.3.5 Type Approval, Product Approval and Limitation Control

2.3.6 Sub-Supplier, Certification Scheme and Change Control

2.4 Change Control and Traceability

2.4.1 Change Identification and Classification

2.4.2 Change Impact Assessment

2.4.3 Revision, Configuration and Evidence Traceability

2.4.4 Interface and Integration Change Control

2.4.5 Implementation, Verification and Survey Close-Out

2.4.6 In-Service Changes, Limitations and Record Retention

This section defines the requirements for main propulsion machinery and the machinery systems directly required to produce, transmit, control and protect propulsion power. Main propulsion machinery shall be suitable for the intended service, assigned notation, operating profile, machinery arrangement, environmental conditions, control concept and failure con...

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Subsections

3.1 Main Engine Arrangement

3.1.1 Engine Identity, Boundary and Installation Basis

3.1.2 Foundations, Seating and Holding-Down Arrangements

3.1.3 Access, Maintenance, Removal and Survey Arrangements

3.1.4 Ventilation, Combustion Air, Exhaust and Thermal Arrangement

3.1.5 Connected Services and Interface Arrangements

3.1.6 Installation Verification, As-Built Records and Limitations

3.2 Power Rating and Operating Limits

3.2.1 Rated Power, Speed and Duty Declaration

3.2.2 Continuous, Intermittent, Emergency and Restricted Ratings

3.2.3 Environmental Derating and Installation Conditions

3.2.4 Operating Envelope, Barred Ranges and Limit Schedule

3.2.5 Overload, Transient Response and Load Acceptance

3.2.6 Protection Settings, Trial Confirmation and Limit Records

3.3 Starting, Reversing and Control

3.3.1 Starting Readiness and Starting-Energy Arrangements

3.3.2 Stopping, Emergency Stop and Restart Control

3.3.3 Reversing, Astern Operation and Manoeuvring Sequence

3.3.4 Remote, Local and Emergency Control Stations

3.3.5 Interlocks, Permissives and Control Failure Response

3.3.6 Functional Testing, Trials and Control Records

3.4 Lubrication, Cooling and Exhaust Interfaces

3.4.1 Lubricating Oil Supply, Cleanliness and Protection Interface

3.4.2 Cooling Water Capacity, Temperature Control and Redundancy Interface

3.4.3 Exhaust Gas Routing, Back Pressure and Thermal Protection Interface

3.4.4 Combustion Air, Charge Air and Machinery-Space Ventilation Interface

3.4.5 Isolation, Leakage, Flexible Connection and Support Arrangement Interface

3.4.6 Commissioning, Monitoring and Interface Close-Out Records

3.5 Protection and Shutdown Functions

3.5.1 Protection Philosophy, Cause-and-Effect and Safety Function Boundary

3.5.2 Alarm, Indication and Operator Response Requirements

3.5.3 Load Reduction, Slowdown and Standby Start Functions

3.5.4 Shutdown, Trip and Emergency Stop Functions

3.5.5 Overspeed, Crankcase, Fire-Risk and Special Hazard Protection

3.5.6 Testing, Configuration Control and Protection Records

This section defines the requirements for auxiliary machinery serving propulsion support, electrical power generation, steering support, pressure and fluid services, safety systems, pollution-prevention functions and ordinary ship-service machinery where the function is relevant to class. Auxiliary machinery shall be suitable for the intended service, operat...

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Subsections

4.1 Auxiliary Engines and Generating Sets

4.1.1 Identity, Rating, Duty and Service Role

4.1.2 Generator Load Interface, Governor Response and Power Quality

4.1.3 Installation, Support Systems and Machinery-Space Interfaces

4.1.4 Protection, Monitoring and Safety Devices

4.1.5 Testing, Load Demonstration and Survey Close-Out

4.1.6 Records, Maintenance, Replacement and Change Control

4.2 Pumps, Compressors and Fans

4.2.1 Service Classification, Medium and Duty Boundary

4.2.2 Capacity, Head, Pressure and Operating Envelope

4.2.3 Arrangement, Suction and Discharge Integration

4.2.4 Standby, Redundancy, Isolation and Failure Response

4.2.5 Protection, Monitoring, Relief and Hazard Control

4.2.6 Certification, Testing, Maintenance and Change Records

4.3 Redundancy and Standby Arrangements

4.3.1 Function Criticality and Failure Consequence Basis

4.3.2 Remaining Capacity and Load Sharing After Failure

4.3.3 Common-Cause Dependencies and Segregation

4.3.4 Standby Readiness, Starting and Changeover

4.3.5 Isolation, Maintenance and Temporary Degraded Operation

4.3.6 Verification, Periodic Testing and Lifecycle Records

4.4 Foundations and Local Supports

4.4.1 Equipment Load Data and Foundation Boundary

4.4.2 Load Path, Local Reinforcement and Structural Continuity

4.4.3 Vibration, Alignment and Resilient Mounting Control

4.4.4 Fastening, Chocking, Bolting and Local Attachment Details

4.4.5 Installation, Survey Access and Interface Support

4.4.6 Testing, As-Built Records and Lifecycle Change Control

This section defines the requirements for propulsion shafting, couplings, bearings, propellers, stern tube arrangements, seals, lubrication interfaces, thrusters and azimuthing propulsion units. The shafting and propulsor arrangement shall be suitable for transmitting power and thrust safely under the approved operating envelope, including normal service, ma...

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Subsections

5.1 Shaft Line Arrangement and Alignment

5.1.1 Shaft Line Boundary and Alignment Model

5.1.2 Bearing Reactions and Load Distribution

5.1.3 Hull Deflection, Thermal Growth and Installation Condition

5.1.4 Alignment Tolerances, Measurements and Correction Procedure

5.1.5 Vibration, Barred Ranges and Operating Restrictions

5.1.6 Installation, Trials, Records and Change Control

5.1.7 Aftmost Bearing Lubrication and Relative Slope Criteria

5.2 Shafts, Couplings and Bearings

5.2.1 Material, Certification and Traceability

5.2.2 Shaft Strength, Diameter and Fatigue Basis

5.2.3 Couplings, Fits and Torque Transfer

5.2.4 Bearings, Lubrication and Load Capacity

5.2.5 Manufacture, NDT, Fitting and Assembly Controls

5.2.6 Testing, Records and Lifecycle Change Control

5.3 Propellers and Propeller Attachments

5.3.1 Propeller Scope, Type and Load Basis

5.3.2 Blade Strength, Geometry and Material Basis

5.3.3 Propeller Attachment, Keyed and Keyless Fits

5.3.4 Built-up, Controllable Pitch and Special Propellers

5.3.5 Inspection, Balancing, Damage and Repair Controls

5.3.6 Tests, Trials, Records and Lifecycle Change Control

5.4 Stern Tube, Seals and Lubrication

5.4.1 Stern Tube and Bearing Arrangement Boundary

5.4.2 Sealing Arrangement and Boundary Protection

5.4.3 Lubrication Medium, Cleanliness and Supply

5.4.4 Bearing Load, Pressure, Clearance and Temperature

5.4.5 Monitoring, Alarms, Leakage and Environmental Control

5.4.6 Installation, Tests, Records and Lifecycle Change Control

5.5 Thrusters and Azimuthing Units

5.5.1 Unit Scope, Rating and Operating Envelope

5.5.2 Foundation, Hull Opening and Load Transfer

5.5.3 Transmission, Propulsor, Bearings and Seals

5.5.4 Steering, Azimuthing Control and Protection

5.5.5 Installation, Functional Tests and Sea Trials

5.5.6 Records, Limitations and Lifecycle Change Control

This section defines the requirements for boilers, steam systems, pressure vessels, heat exchangers, thermal oil systems and associated pressure-retaining, temperature-control and safety devices. The pressure and thermal arrangement shall be suitable for the approved design pressure, maximum working pressure, design temperature, fluid, heat duty, material, c...

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Subsections

6.1 Pressure Design Basis

6.1.1 Pressure Boundary and Design Inputs

6.1.2 Design Pressure and Design Temperature

6.1.3 Materials, Allowable Stress and Joint Efficiency

6.1.4 Corrosion, Erosion and Minimum Thickness

6.1.5 Test Pressure, Relief Setting and Safety Margin

6.1.6 Records, Limitations and Change Triggers

6.2 Boilers and Steam Systems

6.2.1 Boiler Scope, Type and Steam System Boundary

6.2.2 Pressure Parts, Materials and Construction Evidence

6.2.3 Safety Valves, Relief Capacity and Discharge

6.2.4 Water Level, Feed Water and Blowdown Protection

6.2.5 Combustion, Heat Source, Controls and Alarms

6.2.6 Boiler Tests, Surveys, Records and Change Control

6.3 Pressure Vessels and Heat Exchangers

6.3.1 Equipment Scope, Category and Pressure Side Boundary

6.3.2 Pressure-Retaining Parts, Materials and Manufacturing Evidence

6.3.3 Heat-Transfer Duty, Flow and Fouling Basis

6.3.4 Relief, Isolation, Drains, Vents and Leakage Control

6.3.5 Installation, Supports, Thermal Expansion and Access

6.3.6 Tests, Certificates, Records and Change Control

6.4 Thermal Oil Systems

6.4.1 System Scope, Thermal Oil Fluid and Service Boundary

6.4.2 Expansion, Pressurisation, Venting and Drainage

6.4.3 Circulation, Flow, Heater Protection and Standby Basis

6.4.4 Heat Source, Temperature Control, Alarms and Shutdowns

6.4.5 Leakage Protection, Insulation and Fire Safety

6.4.6 Tests, Fluid Condition, Records and Change Control

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