Bunkering

Bunkering is the operation of taking fuel oil, lubricating oil, or marine gas oil aboard a vessel to replenish stocks consumed or required for the forthcoming voyage. The process involves connecting flexible hoses or hard arms between the bunker barge or shore installation and the ship's bunker manifold, transferring predetermined quantities to designated tanks, and monitoring for overflow, pollution, and stability changes throughout. MARPOL Annex I regulation 38 requires that all transfers of oil are supervised and that the Oil Record Book Part I is accurately completed. MARPOL Annex VI regulation 18 mandates the retention of bunker delivery notes and fuel oil samples for at least three years to demonstrate compliance with fuel sulphur content limits — currently 0.50% m/m globally and 0.10% m/m in Emission Control Areas (ECAs). SOLAS VI/5.1 requires the provision of a bunkering plan before the operation begins. The chief officer monitors trim and stability continuously during bunkering, and the engine room officer monitors tank capacities and overflow alarms. Pollution incidents during bunkering are reportable to the port state authority under MARPOL and can result in substantial fines, detention, and prosecution.