This document was published on 1 September 2023 and became effective on the same date.
The September 2023 version updates the requirements covering the technological advancements, assessments, and studies that have been developed by the industry.
The international regulations pertaining to gas or other low flashpoint fueled ships, other than those covered by the IGC Code, are those included in the IMO International Code of Safety for Ships Using Gases or Other Low Flashpoint Fuels (IGF Code), which entered into force on 1 January 2017.
The IGF Code has been incorporated along with ABS requirements in Part 5C, Chapter 13 of the ABS Rules for Building and Classing Marine Vessels (Marine Vessel Rules).
The IGF Code currently only includes detailed prescriptive requirements for natural gas (methane) applications.
All other low flashpoint fuels or gases must demonstrate an equivalent level of safety by application of the Alternative Design methodology as specified in International Convention for the Safety of Life at Sea (SOLAS) Chapter II-1 Regulation 55 and guidelines referenced by footnote MSC.1/ Circ.1212 or associated guidelines MSC.1/Circ.1455.
Where other prescriptive IMO requirements exist for specific gases or other low flashpoint fuels, either by regulation, or as interim guidelines, these may be applied in lieu of the Alternative Design criteria, subject to agreement by the flag Administration.
Currently, no such IMO instruments exist for the use of anhydrous ammonia as fuel.
This document provides guidance for the design, construction, and survey of vessels utilizing anhydrous ammonia (ammonia) as fuel.
This document focuses on systems and arrangements provided for the use of ammonia for propulsion and auxiliary systems.
Where anhydrous ammonia is intended for use as fuel on vessels carrying passengers on board, e.g., passenger vessels, ferries etc., additional design and operational mitigations are to be provided for the protection of passengers from ammonia exposure.
The adequacy of the mitigations is to be evaluated during vessel specific risk analysis.
This document provides Classification requirements for the arrangements, construction, installation and survey of machinery, equipment and systems for vessels operating with ammonia as fuel to minimize risks to the vessel, crew and environment.
This document is to be applied to both new construction and existing vessel conversions, regardless of size, including those of less than 500 tons gross tonnage, utilizing ammonia as fuel.
This document applies to ships covered by the IGF Code. ABS will consider application of this document to ships falling under the scope of the IGC Code on a case-by-case basis, provided such proposals are arranged in accordance with the requirements of the IGC Code and demonstrate the same level of safety as natural gas and with agreement of the flag Administration.