Your examiner asks: "Walk me through the fuel changeover procedure and logging required when entering an ECA."

A. A documented changeover procedure must be followed before ECA entry, completed in good time so that all fuel oil systems are flushed of higher-sulphur fuel before entry; the date, time, position and fuel oil tank quantities at the time of changeover (both entry and exit) must be logged — this changeover log is a specific item PSC and class auditors check, and is also entered in/cross-referenced with the Oil Record Book.

B. Fuel changeover may be completed instantaneously at the ECA boundary with no advance flushing of fuel lines required.

C. Only the changeover into the ECA needs to be logged; the changeover back to higher-sulphur fuel on exit has no logging requirement.

D. Fuel changeover logging is a class society recommendation only, with no regulatory basis under Annex VI.

A. An Emission Control Area (ECA) is a designated sea area (e.g. Baltic Sea, North Sea, North American coasts, Caribbean) with stricter SOx (and in some, NOx Tier III) limits than the global rule. The global sulphur cap is 0.50% m/m (since 1 January 2020, IMO 2020); inside a SOx ECA the limit is stricter, commonly cited at 0.10% m/m, requiring either low-sulphur fuel, approved equivalent means (e.g. an exhaust gas cleaning/scrubber system), or use of an alternative fuel meeting the limit.

B. ECAs apply only to NOx and have no relationship to fuel sulphur content at all.

C. The global sulphur cap and the ECA sulphur cap are numerically identical; ECAs only add extra reporting paperwork.

D. ECA status applies only to passenger vessels; cargo ships transiting the same waters are exempt from the ECA sulphur limit.

A. The Bunker Delivery Note (BDN) records the supplied fuel's quantity, sulphur content declaration and other specification details and must be retained on board for at least 3 years; a representative MARPOL delivery sample, sealed and signed by ship and supplier representatives, must be retained on board for at least 12 months (or until the fuel is fully consumed if that is sooner, per the applicable retention rule) to allow verification testing if the fuel's compliance is disputed.

B. The Bunker Delivery Note and fuel sample are commercial documents only, with no MARPOL retention requirement.

C. The fuel sample need only be retained until the vessel leaves the bunkering port.

D. Only the supplier is required to retain a fuel sample; the ship has no sample retention obligation.