The effectiveness of ‘drencher systems’ per Resolution A.123(V) has been questioned for many years. This report presents a review of potential commercially available alternative systems and their expected performance efficiency, water consumption and estimated installation costs. Additionally, large‑scale fire tests were performed for selected systems.

Three main alternative fire-extinguishing systems were identified:

• Compressed Air Foam Systems (CAFS)
• Foam-water sprinkler and foam‑water spray systems; and
• Water curtains.

Water curtains was the least expensive system, but the areas sub‑divided by the water curtains require cargo spacing, resulting in significant yearly losses in income for a ship owner. Furthermore, water curtains were de-selected since they cannot replace a conventional fire-extinguishing system.

The installation cost for the selected CAFS was very high and it gave limited fire suppression in the large‑scale fire tests, probably due to the limited discharge density of 2.4 mm/min.

The system per MSC.1/Circ.1430 (10 mm/min) had superior performance while the system per Resolution A.123(V) (5 mm/min) and the foam‑water spray system (6.5 mm/min + foam) limited the fire size to some degrees. However, for a potential spill fire scenario, improvements of foam could be relevant.

Foam injection could be an alternative, but no new system was recommended to be required.