Controlled technical rules for classification and survey work.
HCS Rules form the technical basis for classification activities performed within their applicable scope. Users should verify that the edition and part being relied upon is current and applicable to the vessel, service and technical decision under review.
Open the relevant rule part directly.
The documents below are the rule parts currently published on the HCS website. Rule application remains subject to vessel type, construction, machinery, class notation, survey status, applicable statutory requirements and any approved technical interpretation or revision issued by HCS.
HCS Class Rules library.
Open a rule part in your browser or download a copy for technical reference.
General Requirements
Materials and Welding
Hull Construction & Equipment
Specialized Vessels
Machinery Installations
Electrical Installations
Refrigerating Installations & Automation
Automation and Remote Control
Fire Protection, Detection and Extinction
Shipboard Cyber Resilience
HCS RN 001 · REVISION 1.0Class Numbers & Class Notations
Approved HCS notation system and catalogue. Effective 23 October 2026.
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RO Code Governance and Flag Oversight
Rules are applied within a documented technical context.
Need help identifying the applicable HCS Rule?
Send the vessel name, IMO number, ship type, technical subject and relevant drawing / document reference to HCS Technical Desk.