Japanese classification society ClassNK has amended its Rules and Guidance for the Survey and Construction of Steel Ships.

The classification society constantly revises the rules to ensure they are in line with the latest results from research and development projects, industry requests, regulatory requirements, damage investigation feedback, international convention changes and International Association of Classification Societies’ (IACS) unified requirements (UR).

Discover B2B Marketing That Performs

Combine business intelligence and editorial excellence to reach engaged professionals across 36 leading media platforms.

Find out more

Following feedback from damage investigations, ClassNK has made amendments to the welding for cross-joints subject to high stress, towing winch emergency release systems and arrangement, connection and protection of piping systems.

Responding to industry requests, some amendments were related to the steels subject to special requirements for ammonia carriers, application clarification of the requirements for fire protection and extinction and the guidance associated to drip tray alarms provided for exhaust gas cleaning systems.

In response to changes in international conventions, ClassNK adjusted rules related to damage stability, winches for all lifeboats apart from the free-fall lifeboats and the Global Maritime Distress and Safety System (GMDSS) modernisation.

The classification society also amended the rules and guidance associated with the condition-based maintenance scheme for machinery, materials used for the principal components of diesel engines and environmental tests for automatic equipment.

GlobalData Strategic Intelligence

US Tariffs are shifting - will you react or anticipate?

Don’t let policy changes catch you off guard. Stay proactive with real-time data and expert analysis.

By GlobalData

The new rules and guidance are available on the ClassNK website.

In July 2019, ClassNK issued guidelines for ships using methyl, ethyl alcohol and liquefied petroleum gas (LPG) low-flashpoint fuels to reduce greenhouse gas emissions.

Ship Technology Excellence Awards - Nominations Closed

Nominations are now closed for the Ship Technology Excellence Awards. A big thanks to all the organisations that entered – your response has been outstanding, showcasing exceptional innovation, leadership, and impact.

Excellence in Action
From automated chartering invoices to EU ETS and CII management, Ankeri Solutions’ maritime SaaS platform has earned three Ship Technology Excellence Awards for 2025. See how Ankeri is helping shipowners and charterers boost efficiency, cut emissions, and collaborate better across complex global fleets.

Discover the Impact