MARPOL Annex I

MARPOL Annex I prevents pollution by oil from machinery spaces and oil cargo. It sets the 15 ppm limit for oily bilge water discharge through approved oil filtering equipment with a 15 ppm alarm, governs oil tanker cargo and slop handling, and mandates the oil record book in parts I and II. Structural rules require double hulls for oil tankers and segregated ballast tanks. The Annex defines special areas with stricter discharge limits and requires the Shipboard Oil Pollution Emergency Plan. It entered into force on 2 October 1983.