Marine Pollution Prevention and Environmental Protection
Core concepts
MARPOL dominates this domain. Know Annex I oil: the 15 ppm oily-water separator and oil discharge monitoring equipment, the Oil Record Book parts, and the special area restrictions. Annex II noxious liquid substances and the prewash requirement; Annex III harmful packaged goods; Annex IV sewage and the treatment standards; Annex V garbage and the discharge table; Annex VI air pollution, sulphur limits, emission control areas, nitrogen oxide tiers and the sulphur cap compliance options including scrubbers and fuel changeover. Understand the Bunker Convention and civil liability, the ballast water management convention and the D-2 standard, antifouling, ship recycling under the Hong Kong Convention, and the SOPEP and shipboard oil pollution emergency plan. Environmental awareness includes energy efficiency: EEDI, SEEMP and CII.
Traps
A common error is assuming treated sewage may be discharged anywhere; distance and speed conditions still apply outside special areas, and stricter rules apply within them. Do not confuse the 15 ppm equipment standard with the older 100 ppm standard. Questions on Annex VI often test that sulphur limits apply at the point of combustion and that non-compliant fuel must not be carried unless a scrubber is fitted. Garbage categories are frequently mixed up.
Worked rule of thumb
Memorise Annex V as a discharge table by category and area. For example, food waste comminuted to less than 25 mm may generally be discharged outside 3 nautical miles from land, and outside 12 nautical miles if not comminuted; most other garbage is prohibited overboard.