Your examiner asks: "What is the difference between an accidental and an operational oil discharge under MARPOL, and does Annex I treat them the same way?"

A. Operational discharges (e.g. controlled bilge/ballast discharge via an approved OWS within permitted limits) are permitted subject to the conditions in Annex I. Accidental discharges (e.g. from collision, grounding, hull failure) are not "permitted" in the same sense but trigger an immediate reporting obligation under Article 8/Protocol I, and the ship's SOPEP response procedure, rather than being judged against the routine discharge criteria.

B. MARPOL Annex I applies identical discharge limits to both — any discharge, whether accidental or operational, is judged solely against the 15 ppm limit.

C. Accidental discharges are entirely outside MARPOL's scope and are governed only by the Civil Liability Convention, with no Annex I reporting duty.

D. Operational discharges require no Oil Record Book entry; only accidental discharges must be logged.

A. Ships of 400 GT and above must carry an Oil Record Book (Part I, machinery space operations) and a SOPEP (Shipboard Oil Pollution Emergency Plan); tankers of 150 GT+ also need Part II (cargo/ballast operations). All oil tankers and ships of 400 GT+ must hold an IOPP (International Oil Pollution Prevention) Certificate. Oil filtering equipment/oily water separator is required, generally limited to discharging at no more than 15 ppm oil content outside special areas.

B. Only oil tankers above 5,000 GT need an Oil Record Book. SOPEP is voluntary and recommended only by the company P&I Club.

C. All ships regardless of size must carry an IOPP Certificate and a Garbage Record Book under Annex I.

D. The Oil Record Book is only required while the vessel is within a Special Area; outside Special Areas no oil-discharge record-keeping is required.

A. A SOPEP contains: the master's reporting procedure and authorities to contact (including national contact lists, which must be updated periodically — commonly every 3 months); a list of shipboard officials responsible for combating spills; procedures for reporting oil pollution incidents; steps to control/minimise the discharge; coordination with national/local authorities; and equipment/material lists for spill response on board.

B. A SOPEP only contains a list of approved dispersant chemicals and their application rates.

C. A SOPEP is a class society survey checklist used solely during the annual Annex I survey, with no operational content.

D. A SOPEP applies only to oil tankers; non-tankers carry a SMPEP (Shipboard Marine Pollution Emergency Plan) instead and have no SOPEP requirement.