Press Release

02 March 2026

Tokyo – ClassNK has issued approvals in principle (AiPs) for the concept designs of Bulk Carrier installed with a Membrane-based Onboard Carbon Capture and Storage System (OCCS) and 83,000m3 Ammonia Carrier with IMO Type B Independent Tank developed by Oshima Shipbuilding Co., Ltd. These AiPs demonstrate its feasibility from regulatory and safety perspectives.

The recipients of the AiPs, as well as the applicable rules and guidelines, are as follows.

-Bulk Carrier installed with Membrane-based OCCS
Recipients: Oshima Shipbuilding Co., Ltd.; Fuji Electric Co., Ltd.
Applicable rules / guidelines:
In October last year, ClassNK published the “Guidelines for Onboard CO2 Capture and Storage System (Edition 2.0)”*1, which, the world’s first to include requirements for OCCS utilizing membrane separation method—an approach that is anticipated to have a lower power demand and smaller installation space than amine absorption. The concept design for this vessel was reviewed in accordance with these guidelines.

-83,000m3 Ammonia Carrier with IMO Type B Independent Tank
Recipient: Oshima Shipbuilding Co., Ltd.
Applicable rules / guidelines:
The IMO Type B Independent Tank defined in the IGC Code*2 offers advantages in cargo capacity and outfitting efficiency but requires a significantly high level of engineering sophistication compared with other cargo tank types. ClassNK conducted its review of this concept design based on Part N of its "Rules and Guidance for the Survey and Construction of Steel Ships", which incorporates the IGC Code, along with relevant guidelines.

Following the reviews, ClassNK confirmed that both designs comply with the prescribed requirements and therefore issued the respective AiPs.

ClassNK will continually strive to contribute to advanced decarbonization initiatives through safety assessments and more.


*1 Related Press Release (29 October 2025): ClassNK releases "Guidelines for Onboard CO2 Capture and Storage Systems (Edition 2.0)" - World-first requirements for onboard CO2 capture systems using membrane separation method
https://www.classnk.or.jp/hp/zh/hp_pressrelease.aspx?id=14242&layout=1

*2 international code for the construction and equipment of ships carrying liquefied gases


Vessel Images (courtesy of Oshima Shipbuilding)
-Bulk Carrier installed with Membrane-based OCCS

-83,000m3 Ammonia Carrier with IMO Type B Independent Tank

AiP Handover Ceremony


Approval in Principle (AiP):
At the initial stage of designing or before the specific target ship to be implemented is decided, the design is examined based on the existing regulations such as international conventions and ship classification rules, and an Approval in Principle (AiP) is issued as proof of conformity with requirements. It also prevents rework of regulatory aspects in the post-process, shortens the examination time at the time of class registration, and can be used as a technical basis for external appeal of the design status. For more information, visit our  website.


For inquiries about this press release:
ClassNK Technical Solution Department
Tel: +81-3-5226-2042
E-mail: tsd@classnk.or.jp

For media-related inquiries:
ClassNK Public Relations Team
4-7 Kioi-Cho, Chiyoda-Ku, Tokyo 102-8567 Japan
E-mail: eod@classnk.or.jp

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