The Master's Position in Pollution Prevention
Pollution prevention is not a departmental task delegated to engineers or officers — it is a command responsibility. The Master must understand every discharge regime, have systems in place to prevent accidental discharge, and be able to demonstrate compliance under port State control. Start from the practical sequence: bunkering, sea passage, in-port operations, and garbage.
Fuel Oil — Controlling What Goes Aboard
Before bunkering, confirm the supplier's declared sulphur content against the applicable limit: 0.10% in an ECA (including the North Sea, Baltic, North American, and now the Mediterranean, which became a SOx ECA on 1 May 2025), or 0.50% globally. The Bunker Delivery Note (BDN) is retained on board for three years after delivery. The MARPOL representative sample is retained until the fuel is substantially consumed and for a minimum of 12 months. These are not administrative niceties — they are your primary defence against a flag or port State allegation.
Switching to compliant fuel when entering an ECA must be documented, including tank figures and time/position of the switchover. A Fuel Oil Non-Availability Report (FONAR) exists if compliant fuel cannot be sourced, but it does not excuse non-compliance — it records your best endeavours.
Oily Water — The Annex I Regime
At sea, oily bilge water may only be discharged if processed through approved filtering equipment to <=15 ppm, discharged en route, and outside a Special Area. These conditions are cumulative — all must be met. The Mediterranean is a Special Area under Annex I; no operational Annex I discharge is permitted there. Vessels under 400 GT are not required to carry filtering equipment; their bilge water must be retained and discharged to a reception facility.
For vessels 400 GT and above, every Annex I discharge and all transfers to the bilge holding tank are recorded in the Oil Record Book Part I. Entries are signed by the responsible officer; each completed page is signed by the Master. The ORB is retained for three years after the last entry. An IOPP Certificate is required for vessels 400 GT and above on international voyages, on a five-year survey cycle.
Garbage — The Annex V Regime
No garbage may be discharged into the sea except where Annex V explicitly permits (e.g., food waste beyond specified distances, under specific conditions). In a Special Area — which includes the Mediterranean and the Red Sea (Annex V Special Area from 1 January 2025) — the restrictions are more stringent and most discharges are prohibited entirely.
A Garbage Management Plan is required for vessels 100 GT and above, or those certified to carry 15 or more persons. A Garbage Record Book is required on the same threshold. Entries must be made at the time of each discharge or completed incineration, signed by the officer in charge, with each page signed by the Master.
Maintaining the System at Sea
Avoiding pollution is not just about having the right equipment — it requires a working SMS procedure, trained crew, and a Master who actively oversees operations. Before entering a Special Area or ECA, verify fuel compliance and brief the watch. Before bunkering, rig appropriate spill containment and have response materials at hand. A spill in port, however small, requires immediate reporting to the harbour authority and flag State. Delay or concealment is a criminal matter, not a procedural one.