IACS issues UI for CO₂ fire systems on alcohol-fueled vessels

Eda Zenic -

The International Association of Classification Societies (IACS) has published Unified Interpretation GF21 to standardize fire safety requirements for vessels using methyl or ethyl alcohol as fuel. This interpretation ensures that machinery and fuel preparation spaces have appropriate fire-extinguishing systems that meet SOLAS standards and are capable of handling alcohol fires.

  1. CO₂ Fire Suppression: If a CO₂ system is used, it must release enough CO₂ to fill at least 50% of the largest protected space, including the machinery casing, to ensure effective fire suppression.
  2. Alternative Compliance: Instead of strictly adhering to CO₂ volume requirements, a risk assessment may be conducted. This assessment can consider factors like the amount of methanol onboard and potential fire duration. Based on these factors, alternative fire-extinguishing solutions may be approved by the administration.
  3. Implementation Date: The IACS UI GF21 applies to ships contracted for construction after January 1, 2026, when the MSC.1/Circ.1621 standards are mandated.