IMO adopts new IGF code amendments for low-flashpoint fuels

Eda Zenic -

The International Maritime Organization has issued resolution MSC.551(108) updating the International Code of Safety for Ships Using Gases or Other Low-Flashpoint Fuels (IGF Code).

The resolution introduces new definitions and requirements for ships built on or after 1 January 2026, with a focus on building contracts, keel laying, and delivery dates. It updates procedures for conducting risk assessments in ship design and safety operations, specifying when these assessments are necessary.

Changes in ship design and arrangement include revised regulations for the protective distances around fuel tanks and airlocks, and new specifications for both independent and membrane tanks. Additionally, the resolution updates design requirements for tank vapor pressure and pressure relief systems, including standards for controlling tank pressure and temperature.

Adjustments are made to the calculations for minimum wall thickness in piping and new guidelines are provided for pipe design and construction. For bunkering, the resolution details requirements for the design of bunkering manifolds and dry-disconnect mechanisms to ensure safe fuel transfer, along with mandates for emergency release systems and risk assessments.

New ships are required to have redundancy and segregation in their fuel supply systems, automatic venting of gas supply pipes, and manual shutdown valves for added safety. Design pressures and testing requirements for outer pipes and ducts in fuel systems are also specified.

Fuel preparation rooms are classified as high-category machinery spaces for fire safety, with additional fire-extinguishing equipment required for ships constructed before and after 1 January 2026. The resolution defines hazardous area zones around fuel tanks and equipment for new ships.

Regulations for liquid level indicators and monitoring systems for fuel tanks are updated. Requirements for welding and non-destructive testing of fuel containment systems are revised. Responsibilities for bunkering operations, including transfer procedures and safety measures, are clarified.